Solid State Sodium Ion Batteries for Grid Storage

Today I came across an article about Altech Batteries Limited’s Sodium Chloride Solid State (SCSS) Battery. So I also went to their website and it sounded very interesting until I got to this statement:

The battery plant will produce 1,666 battery packs per annum, rated at 60 KWh each. These CERENERGY® modules are expected to sell for between EUR 700-900 per KWh.

First of all, I think sodium ion batteries are a great match for grid storage: The models available in China right now have slightly lower energy density (in kWh/kg or kWh/l) than LFP or NMC lithium ion batteries, but that is largely irrelevant for stationary applications such as renewable energy storage or grid stabilisation, where specific cost ($/kWh) is more important.

Like LFP batteries, sodium ion batteries do not us Cobalt, a mineral mostly mined in the Democratic Republic of Congo. About 1/5 of production there is from artisanal miners, where child labour and other abuses are common.
Unlike LFP, sodium ion doesn’t use graphite or lithium. By doing without these ingredients and instead using cheaper equivalents such as sodium instead of lithium, iron instead of cobalt and nickel, etc. costs can be lower. As Auke Hoekstra wrote on Twitter on 2024-05-24:

Cheap batteries are a GAME CHANGER for
GRID CONGESTION and for SOLAR and WIND

We are now moving towards $60 on the cell level for LFP and $40/kWh for sodium ion.

Admittedly, there is a bit of a gap between prices at the cell level and the pack level (built from interconnected cells in a case), but almost a year ago, BloombergNEF already reported that:

The price of lithium-ion battery packs has dropped 14% to a record low of $139/kWh (…)
(“BloombergNEF’s annual battery price survey finds a 14% drop from 2022 to 2023”, 2023-11-27)

Read that again and then look at Cerenergy’s promise of offering similar technology at $770-990/kWh. The lower end of that range is the average pack level price that BloombergNEF listed for the year 2013, eleven years ago.

Yes, Cerenergy is solid state instead of liquid electrolyte, but that’s the only significant difference other than a price that’s an order of a magnitude higher, probably due to the high cost of the solid state electrolyte, but also the use of nickel instead of iron-based cathodes that current sodium ion batteries tend to use.

When others tout solid state technology for batteries (i.e. batteries without liquid electrolyte), the main selling point tends to be higher energy density per kg, which is still important for EVs, especially in locations with a not very dense charging network. However, when targeting the grid storage market, this benefit becomes irrelevant: Nobody really cares if some shipping containers full of batteries installed next to an electricity substation weigh 6t each or 10t each. However, it makes a huge difference if they cost $80,000 each or $800,000 each because it means you can install 10 MWh of storage with cheaper technology for the price of 1 MWh with the more expensive option. That’s a game changer!

Perhaps I am missing something in this picture, but I am yet to be convinced of the clear benefit of more expensive solid state batteries over low cost conventional chemistry batteries for the bulk of the market, both for lithium and for sodium chemistries, and I don’t see how that will change any time soon.

There may be a market for solid state lithium batteries for niche markets such as electric airplanes, but it’s simply going to be too expensive for grid storage or for most of the EV market for the foreseeable future.

Toyota’s solid state battery plans

Under Toyota Motor Corp’s new CEO the company finally seems to put more emphasis on battery electric vehicles (BEVs). However, this does not translate into short term product availability: The bZ4X is the only battery electric car Toyota is selling outside of China right now (in the Chinese market Toyota is also offering the bZ3 which is based on a battery electric platform by BYD, the leading Chinese BEV maker).

The wrong platform
Toyota is working on a new dedicated battery electric platform. The e-TNGA platform that the bZ4X is based on is a derivative of Toyota’s ICE-based TNGA platform. A platform that must cover both ICE and BEV is not ideal for either: In a BEV drivetrain, the heaviest part is the battery built into the floor of the car and there is no need for a classic engine compartment while in an ICE car the heaviest part are the engine+gearbox at the front. Build something that can cope with either and you end up with wasted space and extra weight that isn’t needed for one of the variants, plus it costs more to build.

Other manufacturers have already made the switch to BEV-only platforms. For example, VW initially offered the e-Golf based on the platform of the regular ICE Golf. In 2020 it discontinued the e-Golf and replaced it with the ID.3 which was based on a BEV-only platform (MEB). Toyota models based on the future BEV-only platform will be released in 2025 or 2026, meaning Toyota will make this architectural switch 5-6 years after VW!

Under its previous CEO Toyota was in no hurry to go battery electric. Instead it tried to maximize sales of its hybrid models which after all still offered the best fuel economy amongst ICE cars. The longer buyers stayed away from BEVs and stuck with ICEs the more Toyota could benefit from its ICE hybrid technology against less sophisticated non-hybrid ICE cars. Toyota was gambling on the absence of progress while we are heading full steam into climate disaster.

While Toyota was selling gasoline-powered cars it kept talking about future technology, including hydrogen fuel cells (HFC) and solid-state batteries. In 2014 it had launched the Toyota Mirai to showcase HFC but the technology was too expensive to build to be able to make a profit. HFC cars will need a completely new fuel infrastructure to be built from scratch.

Besides HFC Toyota is also working on hydrogen ICE cars and is researching e-fuels (synthetic hydrocarbons made using green hydrogen and CO2) for ICE cars. It’s like the company wants to try every possible alternative to BEVs instead of focussing on the most promising approach as Tesla, BYD, VW and other manufacturers do.

Solid-state batteries (SSB) hold the promise of higher energy density compared to current types of lithium ion batteries by using a solid electrolyte instead of a liquid but SSBs are still far from market-ready. Toyota only expects to be able to commercialize them by 2027 or 2028. A lot could happen until then.

When Toyota was expecting market penetration of BEVs to remain slow until 2030, waiting for solid state batteries to reach maturity and not custom-designing a platform specifically for BEVs before then seemed to make sense for them, but they completely underestimated the speed at which consumers in international markets are now making the switch. Only one fifth of one percent of Toyotas sold in the first half of 2023 were BEVs, even though one in 4 cars sold in China and one in 5 cars sold in major European markets are already BEVs. The biggest car manufacturer in the world is not even in the top 10 of BEV makers. It could be Nokia and smartphones all over. By next year BEVs will already reach higher market share in major export markets than Toyota had expected by 2030. To keep up next year Toyota would have had to make different decisions 5 years ago and because of this, it will fall further behind. Can it still catch up?

The cure for range anxiety
Recently Toyota has been talking about SSBs and technical breakthroughs:

Kaita said the company had developed ways to make batteries more durable and believed it could now make a solid-state battery with a range of 1,200km (745 miles) that could charge in 10 minutes or less.
(Guardian, 2023-07-04)

Even if we assume that they can make SSB work by 2028, a battery with a range of 1,200 km that can be charged in 10 minutes makes no sense: If it can be really charged that quickly a much smaller battery would be a better fit. That way you could get 400 km or 600 km of range at 1/3 or half the cost and weight penalty. Nobody needs that much range if charging takes no longer than a toilet stop or how long it takes to buy a cup of coffee unless you’re trying to cross the Gobi desert.

Range anxiety has been an obstacle to the spread of BEVs but the cure is not super sized batteries, it’s a denser charging network equipped with high speed chargers. Japan still has a lot of work to do here, both in terms of the number of chargers and their maximum power output. Highway service areas and also most Nissan dealers tend to have fast DC chargers installed but Toyota dealers by and large only offer 200 V AC charging which barely covers plug-in hybrids (PHEVs) but not BEVS. Most public car parks do not include charging spots.

This must change and will change. A BEV with 1,200 km of range would have made perfect sense 3 years ago when the charging situation was even worse. Five years from now there will be far more DC fast chargers and they will be everywhere. Consequently the price of BEVs will be a much bigger factor in buying decisions than ultimate range. Chinese manufacturers have been using lower cost LFP batteries instead of the more costly NCM batteries that the bZ4X uses and even cheaper sodium ion batteries (NIB) are now being commercialized.

Are solid-state batteries the game changer?
Talking about super long range BEVs is supposed to send two messages:
1) Toyota will be a future technology leader again, so please don’t sell your shares yet and
2) Current BEVs don’t have enough range for peace of mind, so your next car should still be a hybrid ICE car.

It remains to be seen if SSBs will work out for Toyota and Honda. It can be a long way from lab results to mass market deployment. I am not saying that there won’t be a market for SSBs (once somebody can make them work): There will be, especially at the high end. But for the volume market, the game will be decided via the density of the charging network (especially using high output chargers) in combination with lower cost battery technologies that will eventually make BEVs cheaper than ICEs.

Give me a BEV with 400 km of range that can add 300 km of charge in 20 minutes and costs no more to buy and far less to run than an ICE car: When that happens then it will be “Game Over” for gasoline and diesel cars.

Anti-battery propaganda on Facebook

Perhaps one of your Facebook friends posted this piece of propaganda on their feed:

This machine is required to move 500 tons of earth/ore which will be refined into ONE lithium car battery.
It burns 900-1000 gallons of fuel in a 12 hour shift.
Lithium is refined from Ore using sulfuric acid.
A battery in an electric car, lets say an average Tesla, is made of …
25 pounds of lithium,
60 pounds of nickel,
44 pounds of manganese,
30 pounds of cobalt,
200 pounds of copper,
400 pounds of aluminum, steel, and plastic etc.
That averages 750-1,000 pounds of minerals, that had to be mined and processed into a battery that merely stores electricity …
Electricity which is generated by oil, gas, coal, nuclear, or water (and a tiny fraction of wind and solar)….
That is the truth, about the lie, of “green” energy.
There’s nothing green about the green new deal… Just a lot of pockets being lined and our environment being destroyed by greed, wilful ignorance and selfishness.

Fossil fuel companies have a lot to lose when the energy transition to renewable carbon-free energy sources takes place. Their whole business model of extracting, refining and selling fossil fuels will collapse. The longer they can delay that transition, they more money they can still make. That’s why they have an interest in spreading propaganda like that post above.

No verifiable source is given for any of the numbers in that text but here are some facts: Typical lithium ores (spodumene) in Australia contain about 1-2% Li, meaning for the 12 kg of Li in a car battery listed above you’d have to mine 0.6 to 1.2 t of ore, a far cry from the 500 t claimed. Since they gave no source it’s hard to know how they came up with such distorted figures.

Another major source of lithium are brines which don’t involve any hard rock mining at all though the quantities available are more limited and there are some issues with water consumption. Some companies are working on extracting lithium from geothermal brines as a side product of geothermal energy production.

The majority of Li-ion batteries produced in China these days are based on Lithium iron phosphate (LFP) chemistry, which unlike earlier Li-ion chemistries (NMC, NCA) do not require either cobalt or nickel (the C and N respectively in those acronyms).

In April 2022, LFP batteries in electric vehicles sold in China already outsold other types of Li-ion car batteries by about 2:1 (8.9 GWh vs 4.4 GWh). Tesla’s entry level models made at the Shanghai Gigafactory have switched to LFP too.

By the time most of us will switch to battery electric vehicles, i.e. within the next decade, LFP is likely to be largely superseded by sodium ion batteries. This new chemistry is technically very similar to Li-ion batteries. German battery expert Frank Wunderlich-Pfeiffer (@FrankWunderli13) estimates that by 2026-2028 sodium ion production will exceed lithium ion on a GWh basis. Why is sodium ion cheaper? Unlike lithium which only occurs in special ores that require processing, sodium makes up 39 percent of common table salt. A cubic meter of sea water contains about 14 kg of it. So any time someone says we don’t have enough lithium needed for replacing internal combustion engine (ICE) cars, they are not really looking at where the industry is heading over the next decade.

Talking about the CO2 output from electricity production is a distraction: Even in places like Poland or West Virginia where much of the power is produced from dirty coal, an electric car is responsible for less CO2 output than an ICE car because power plants are far more efficient than car engines. But the main point to remember is that the mix of energy sources will dramatically shift over the next 15-20 years, the lifetime of a car produced today. This will make BEVs cleaner every year. 20 years from now a gasoline powered car will still depend 100% on gasoline and emit as much CO2 in 2042 as it did in 2022. Meanwhile a BEV will run on a zero-carbon mix of solar, wind, nuclear and geothermal once the grid has been fully upgraded.

For those promoting hydrogen as an alternative to BEVs: That’s not going to happen. Hydrogen is not a viable alternative to BEVs, except maybe for trucks, ships and airplanes. There are several reasons for that. For a start, fuel cells are much more expensive than batteries. Battery prices have been falling faster than fuel cell prices which depend on platinum, a rare metal much more costly than any of the metals mentioned when people talk about batteries. Not coincidentally it is also the most widely used material for electrodes of electrolysers. Its second largest producer is Russia, a country now widely sanctioned because of a war that its government started.

BEVs have greatly benefited from demand for batteries by phones, laptops and other mobile devices that have paid for R&D, scaling up production and thus bringing down prices. In fact the first Tesla was based on the same battery cell type that laptops were using at the time. There has been no such synergy for hydrogen. It lacks economy of scale for fuel cells and its distribution system lags far behind while BEVs harness the existing electric grid.

The biggest problem with hydrogen however is the inefficiency of green hydrogen production: It takes roughly three times more electricity for making and consuming hydrogen than to charge and discharge a battery for a given driving distance. That’s because there are more energy losses turning electricity into hydrogen and back into electricity than there are in charging and discharging a battery. Because of this we’d have to build three times more wind turbines and solar panels to replace the same number of ICE cars with hydrogen cars than we would with BEVs. And it’s even worse with ICEs running on hydrogen, a concept promoted by some car manufacturers. On top of that ICEs burning hydrogen have higher smog-forming NOX emissions than ICE cars running on fossil fuels. BEVs don’t release any NOX. If you want clean air, BEVs beat hydrogen hands down.

In a world facing disastrous climate change that urgently needs to get down to zero carbon emissions, ICE cars have no future. Sticking with ICE cars isn’t an option. The choice is not between ICE cars or BEVs, it’s between either BEVs or walking, riding a bicycle or using public transport.

Battery electric cars in Japan

BYD, China’s leading EV maker announced it will release three models for the Japanese market in 2023.

Meanwhile Toyota has only launched a single battery electric model in its domestic market (Toyota bZ4X SUV in 2022) while Nissan has launched two (Nissan Leaf in 2010, Nissan Ariya SUV in 2022). Both brands are still concentrating on gasoline-powered hybrids. The bZ4X is also offered as the Subaru Solterra, with some minor differences from the Toyota-badged model.

Germany’s VW is still holding back on its ID.3 and ID.4 models in Japan, perhaps because it can’t manufacture enough of them even for the European market. The VW group is only represented here in the battery electric market by its luxury brands Audi and Porsche.

Korea’s Hyundai launched the Ioniq 5 this spring, with the larger Ioniq 6 to follow next year.

It looks like 2023 will be an interesting year for BEVs in Japan which until now has been lagging far behind China, North America and Europe in the electric mobility transition.

On my last trip to the UK I was amazed by the number of BEVs of every brand and model I saw in London compared to Tokyo. In 2021, only 10,843 Nissan LEAF and another 8,610 imported electric cars were sold in Japan (about 60% of which were Tesla). That’s under 20,000 in total or 0.2 % of about 6.9 million new cars sold. The UK, with roughly half the population of Japan, bought 190,727 new electric cars the same year. About 1 in every 6 new cars registered in June 2022 in the UK was battery electric.

China recognized that BEVs are a strategic move. Taking the lead will allow them to leapfrog laggards like Toyota who are too wedded to their own past successes to make the necessary transition to a decarbonized future. And it’s not just about the cars: China also added more solar and wind power last year than the rest of the world combined to make it possible to charge these cars without burning fossil fuel. It has heavily invested in long distance HVDC transmission to shift renewable power over great distances while Japan’s grid still consists of separate grids in West Japan, East Japan and in Hokkaido with extremely limited interconnection capacity.

A couple of months ago Toyota upgraded its forecast for electric vehicle sales in 2030 from 2 million a year to 3.5 million a year, which is about one third of its current annual sales. That’s for almost a decade in the future! This suggests it doesn’t see a tipping point where battery electric overtakes internal combustion engines until later in the 2030s. It is hardly surprising then that during the recent G7 conference in Germany, Japan lobbied hard to remove a goal of at least 50% zero-emission vehicles for 2030 from the climate goals communique, presumably at the request of its car industry. Meanwhile 80 percent of new car sales in Norway are already battery electric.

When Toyota launched the bZ4X into the Japanese market this year, it announced a sales goal of only 5,000 units, roughly 1/10 of annual sales of the Toyota RAV4 that it most closely resembles and half of the annual volume of the 11 year old Nissan LEAF.

Furthermore, the bZ4X is not offered for sale to individual consumers who can only get it through leasing contracts. Supposedly this is “to eliminate customer concerns regarding battery performance, maintenance, and residual value.” This move paints long term performance of battery electric cars as a weak point when it isn’t (at least it isn’t with Tesla and other brands). By offering only leasing contracts, Toyota is casting shade on the technology.

At least due to the launch of the bZ4X Toyota will install DC fast chargers at its dealerships by 2025. Many Nissan and Mitsubishi dealers already have 30 kW DC chargers installed and a few have 50 kW chargers (more kW means a faster maximum charging rate) while most Toyota dealers still only offer 200 V AC charging, the most basic of all. The maximum charging rate with 200 V AC is a mere 6 kW. In countries with three phase AC, a 3 phase domestic AC charger that supports 11 kW will be offered by Toyota from the end of 2022. Until then, home charging in your garage or driveway will be limited to the lower rate.

DC charging of the bZ4X can go as fast as 150 kW, but available public DC chargers in Japan right now tend to be limited no more than 50 kW (most of them at car dealerships). For example, right now there are only 4 locations in Central Tokyo that offer 90 kW or more.

I think we will see change in the battery electric vehicle market Japan in the next few years, largely driven by foreign manufacturers introducing new models that Toyota, Nissan and other manufacturers will struggle to compete with. But they will have no choice but to step up the pace of the zero-carbon transition if they don’t want to lose their existing market share here in Japan and in export markets. Otherwise Toyota may become the Nokia of the car industry.

Subaru announces the Solterra, it’s first battery electric car

Perhaps not by coincidence Subaru chose the week of the COP26 climate summit in Glasgow to launch its first battery electric car, the Solterra (the name is a portmanteau of the Latin worlds for sun and earth). To say that it’s based on the same “e-TNGA” electric vehicle platform as the Toyota bZ4X understates how much the two cars have in common: They are basically one and the same car fitted with different badges. Even the wheels are the same. You have to look very carefully at this pair of genetically identical twins until you find a minor detail that distinguishes them: Yes, the rear lights are a bit different.

Toyota owns 20% of Subaru and they have shared models before (Toyota 86 / Subaru BRZ), but I did not expect to see so little recognizable Subaru DNA in their first battery electric vehicle. Yes, there is a four wheel drive model of both the Solterra and the bZ4X and one assumes that Subaru had a hand in design choices for this, but 4WD is by no means unique for BEVs, as models ranging from the Tesla Model 3 to the Volkswagen’s ID.4 are also offered in dual motor 4 wheel drive configurations. Even the hybrid Prius is available in an electric 4WD version.

What seems a little odd is that the non-4WD model is front wheel drive (FWD). In internal combustion engine (ICE) cars, FWD offers some advantages as it saves having to have a long drive shaft between the front engine and the rear differential. The engine and the gearbox can be bolted together and directly drive the nearby front wheels. At the same time the weight of the engine and gearbox provides good traction for the driving wheels, especially in wintry conditions.

With a BEV however, the bulk of the weight is not in the engine but in the battery under the passenger compartment. Thus there is no real advantage in driving the front wheels as opposed to the rear wheels.

An electric motor driving the rear wheels can be very compact, not much bigger than the rear differential and exhaust system in rear wheel drive (RWD) ICE car. Without the traction advantage of the engine over the wheels, it would be better to go for RWD to get more weight on the driving wheels when going uphill or when accelerating. The turning circle would benefit too if the driving wheels don’t have to steer. It is no coincidence that both Tesla and Volkswagen use RWD for their BEVs, in the case of Volkswagen despite the fact that its best selling models such as the Golf and Passat are FWD. So why not Toyota and Subaru? It’s a mystery to me.

Another detail that surprised me was that even though DC charging on this car can reach a respectable 150 kW, AC charging at home is limited to mere 6.6 kW, which is less than for a compact Chevy Bolt. A Golf-sized ID.3 actually handles up to 11 kW. Some of this may be due to the Japanese Chademo charging standard and domestic grid considerations, as Japanese households only have access to 100 V and 200 V single phase current while the US and Europe use the CCS standard and 120 V / 230 V respectively, with 400 V 3-phase AC available anywhere in Europe. So even if there were technical reasons for limited AC charging speeds in Japan, export models should be able to do much better. Toyota may have specified its home charging module to the smallest common denominator, which if true is a bit disappointing.

As for the looks of the Toyota bZ4X / Subaru Solterra, to me they look like a close cousin to the existing Toyota RAV4 that I personally do not find very appealing. However, it is a big seller in the US market and this similarity may help move existing RAV4 owners over to BEV models once they become available some time in 2022.

Toyota has never been enthusiastic about battery electric vehicles. Its official line has been that hybrids are good enough for today and tomorrow we’ll get hydrogen fuel cell cars like its own Toyota Mirai, with all the benefits of battery electric but none of the drawbacks. There was no real space for battery electric in this vision. Toyota clearly over-promised and under-delivered on this strategy: Hybrid cars still spew CO2 into the atmosphere while almost all hydrogen today is made from fossil fuels. Battery electric does much better than that.

In Japan Toyota could rely on the government to help promote its “hybrids today, hydrogen tomorrow” story but in international markets that won’t fly. There the war for the future of the car is over and battery electric won hands down. No other country has a comparable push for hydrogen refuelling infrastructure as Japan has. Even if there were a domestic market for hydrogen cars in Japan, there won’t be any export markets.

Most experts agree that hydrogen vehicles are at least three times less energy efficient than battery electric vehicles, a flaw that would kill them even if the cars and the necessary fueling infrastructure could be built for the same cost, which isn’t the case. Batteries are far cheaper than hydrogen fuel cells and DC chargers are cheaper than electrolysers and hydrogen fuel stations. With battery prices falling further and further, within a few years BEVs will become cheaper to build than hybrid cars. Then the speed of conversion will only be limited by battery production capacity. It’s not clear Toyota will have the right investments in place by then, since it says its future BEVs will eventually be using solid-state batteries, an as yet unproven technology that only exists in the lab.

Until now Toyota had been avoiding BEVs except for the Chinese market, as it hoped buyers would keep buying its existing more profitable hybrid models. That is becoming a risky bet. Drastic changes needed to avoid the worst of a climate disaster no longer seem so radical compared to worldwide measures taken to deal with SARS-CoV-2. Huge numbers of consumers are ready for change. New BEVs by competitors are picking up market share in the US and in Europe. Toyota can no longer afford to wait on the sidelines or it will be seen as becoming irrelevant due to obsolete products.

This new BEV model is a very cautious move by Toyota and Subaru. Instead of competing head on with Tesla or Volkswagen, Toyota and Subaru are entering the BEV market only about as far as they absolutely have to, to still be a credible global player in 2022. The two companies will have to up their stakes to keep up with market developments.

Tesla 4680 cells and bad journalism

Tesla and Pansonic have introduced the new 4680 battery cell that future battery packs for the Model Y and the Cybertruck will be based on. These larger cells will replace the previous 2170 form factor that current Tesla packs are based on, which in turn replaced the 18650 cells that Tesla inherited from the laptop industry.

Some of the articles about the new cell have talked about the 5 times higher capacity of the cells saying it would address the problem of “range anxiety”:

5 times more energy means less range anxiety and more drive time. It means fewer stops on a road trip and a more enjoyable experience.
(Why The Tesla Tabless Battery Is So Good, torquenews.com, 2021-03-30)

Actually, this claim is embarassingly disingenuous.

Yes, the new cells have higher capacity but that’s because they’re bigger, which means a battery pack of a given capacity will be built from fewer but larger cells. The bottom line of capacity by weight or by volume is largely unchanged.

The new cells are 2.2 times the diameter of their predecessors, meaning they will have a cross section 4.8 times larger, so a given number of square meters of floor plan for a particular vehicle will fit 4.8 times fewer of these larger cells with each storing about five times as much energy as their smaller siblings. If you think this makes for 5 times more range then I have a bridge to sell to you 😉

The cells are also 80 mm long instead of 70 mm, but for energy density it’s basically a wash: The energy density per liter or per kg is unlikely to be vastly different.

Another point of confusion is Tesla’s claim that the cells will have five times the capacity but 6 times the power output. Some articles have interpreted that as 20% more range which is not the case. The truth is that the new cells can be discharged 20% faster without overheating but the total amount of energy released is unaffected by that. It’s like saying a car with 120 HP will have 20% more range than a car with 100 HP because it can drive faster. In reality it will burn fuel more quickly while doing so. This is strictly about peak power (energy by time), not total capacity.

The reason for the higher output is that the new batteries are tabless. All cylindrical Li-ion cells consist of two layers with a separator layer in between, wrapped up as a roll. Think of a double ply roll of toilet paper. When Tesla switched from 18650 to 2170, they made the roll wider (65 mm to 70 mm) but also made made the rolled-up sandwiched layers longer, giving the roll 21 mm instead of 18 mm of diameter.

This increased capacity per cell but it also meant that when energy is released in the ion exchange between the two layers in the innermost part of the cell, the current needs to flow round and round the rolled up layers until it reaches the tabs soldered to the exterior from where the power is transferred to the two opposite end of the cell.

The tabless design does away with that. In it, all the top edges of one layer touch each other and the battery pole at the top while the bottom ends of the other layer touch each other and the bottom pole. That dramatically shortens the path of the conductor through which current needs to flow. Internal resistance and waste heat are greatly reduced.

The bigger diameter means that the exterior steel skin of the cell is lighter relative to the reactive parts inside for some weight savings.

Not directly related to the bigger format, the new cells also break new ground by making do without any cobalt in their anodes which rely on nickel instead. Unlike cobalt which is primarily sourced from the Democratic Republic of Congo (a troubled country with huge corruption and human rights problems), Nickel is available from sources worldwide.

Several online articles have also repeated a claim that the new cells have a capacity of 9,000 mAh vs the approximately 5,000 mAh of the 2170 cells. This is way off the mark and must be based on bad arithmetic. To be consistent with Tesla’s claim of 5 times the capacity per cell, it would have to have about 25,000 mAh of capacity. That is also consistent with the quoted capacity of a 4680 cell quoted by a Chinese supplier of Volkswagen, which is also looking at using this format in the future.

LFP cells and the 4680 form factor

Personally, I think it would be great to also see a LFP (Lithium Iron Phosphate) version of 4680 cells. Panasonic announced that they would not be making it, but some of Tesla’s Chinese suppliers might opt for this format, which would work well for entry level models. LFP is a very safe chemistry and has a long cycle life, even if the energy density is somewhat lower.

In any case, it makes more sense for BEVs not to have the highest battery capacities possible but instead for some of the battery inventory to be used for infrastructure to decouple quick charging from available grid capacity: A certain percentage of annual battery production should be installed in chargers instead of in cars. Actually, recycled batteries from scrapped BEVs make a lot of sense for this, but so do different chemistries such as redox flow batteries including iron batteries.

If for example, most cars travel less than 150 km per day it does not really make much sense that they have a large but heavy battery that gives them 400 km of range but costs a lot of money and whose weight increases electricity use when accelerating. More weight also means more tire wear.

On the few days that cars need to travel further than their limited range, they should be able to quickly recharge from supercharger stations that use on-site battery storage to be able to recharge cars regardless of whether the grid has spare capacity at that moment or not. This is a far more efficient use of scarce resources than giving all BEVs a huge battery and makes for a more robust electricity grid.

Expiring the Internal Combustion Engine Car

The US state of Washington has decided to ban sales of new cars with internal combustion engines (ICE, gasoline or diesel) by the year 2030. That is five years earlier than in the state of California.

There are two issues to overcome for a switch to battery electric vehicles (BEVs): supply and charging. Two common worries however will not stand in the way of BEVs replacing ICEs: cost and range. Let me explain.

Battery cost per kWh has been dropping for decades and this trend is expected to continue. This is highly significant: Most parts of a BEV car other than the big battery cost either the same as in an ICE car or they’re cheaper. As a result, the cost of batteries will stop being a major obstacle to adoption of BEVs years before the end of the decade.

The same is true for range. Cheaper batteries mean BEVs with more capacity will become affordable. The higher the capacity, the more km of charge can be replenished in a given number of minutes. For example, a Nissan Leaf with a 40 kWH battery will fast-charge from 0 to 80% in 40 minutes. The Volkswagen ID.4 First Edition with an 82 kWh battery (of which 77 kWh are usable capacity) will go from 5% to 80% charge in 38 minutes, essentially double the charging speed (kWh added per minute) for a battery with twice the range. If you can add hundreds of km of range in the time it takes you to use the toilet and get a cup of coffee then BEVs will be just as viable for long distance trips as ICE cars.

By the middle of this decade there is likely to be a wealth of different battery electric vehicle models on the market, with even BEV laggards such as Toyota, Honda and Subaru having joined in. Production could increase to about 50% of new sales of several large makers (e.g. GM, VW). It will have to scale up further, with the necessary increase in battery production capacity, by the end of the decade to make this happen but it seems eminently doable. Right now, the major bottleneck to ramping up production is not lack of demand but limited availability of battery cells. Every big car maker getting into BEVs will have to build Gigafactories churning out battery packs, or team up with battery makers who make these huge investments.

The more BEV there will be on the road, the more the impact on the electric grid becomes an issue. If you have a car that can cover 300 km or more on a full battery and you can charge at home every night then most likely you will almost never have to seek out a charging station, unlike drivers of ICE cars who regularly will have to fill up at a gas station. BEVs parked in a driveway or garage with a nearby wall socket are much easier to accommodate than cars currently parking in the street or on parking lots, who will require capacity at paid public charging points, which are more likely to be used at daytime. The grid has plenty of capacity for off-peak charging (e.g. overnight), but if a lot of people want to do their charging at superchargers or other fast charging points, this could require an upgrade in generating and transmission capacity to cover a higher daytime peak load. Vehicle to grid technology would help to make this more manageable, as cars sitting idle in a driveway could provide spare power for the few cars doing the odd long distance trip.

In any case, I see a date roughly around 2030 as the Goldilocks target for a phase-out of ICE-powered new cars. For high income countries this goal is neither too unambitious nor too unrealistically aggressive. Japan’s goal by contrast for a phase-out by the mid-2030s that still allows hybrid ICEs like the Toyota Prius after that date is quite unambitious. By setting the bar that low, prime minister Suga pleases Toyota, as expected, allowing it to keep selling dated technology in Japan that they will no longer be able to sell elsewhere. That puts Japan in the company of developing countries, which will most likely continue using ICE cars exported from rich countries for years to come.

The sooner rich countries switch to BEVs, the shorter the long tail of CO2-emitting ICE cars still running in poorer countries will be.

Toyota is yielding the future to Tesla and other EV makers

In October 2019, Toyota along with General Motors and Fiat Chrysler sided with the Trump administration in its effort to strip the state of California of its ability to set tighter vehicle emission standards than set by the Federal government. In July 2019, several other car makers including Ford, Honda and Volkswagen had sided with California.

This seemed a very odd move for a company whose iconic Prius hybrid was once seen as a way for people ranging from middle class families to Hollywood stars to show their green credentials. Toyota seems on the wrong side of history now.

I also drive a Prius which I bought almost 12 years ago. When it came out, it was way ahead of everything else: Three times as fuel efficient but more spacious and more reliable than my Audi. It wowed me when I first saw one and later when I first test-drove a friend’s. As an engineer I appreciated the clever technology behind it and as a family man I could rely on it for affordable transport.

However, if I were to buy a car now, I’d have a hard time making up my mind. If Tesla had designed its Model 3 as a mid-size hatchback (like the Prius) instead of giving it a trunk, the choice would be easy. Tesla seems set to address that criticism with its forthcoming Model Y, which will be like a slightly larger hatchback version of the Model 3. If Toyota had redesigned its Prius as a battery electric vehicle (BEV) with at least 300 km of range, the choice would have been even easier. The problem is, Toyota isn’t going to do that and I think I understand why.

I have talked to Toyota dealer sales representatives who came to sell me a new Toyota and when I mentioned about electric vehicles, they kept telling me the time wasn’t ripe for that yet, that infrastructure was too spotty and range too short. I would be better off getting another hybrid as the next car. And Toyota has many hybrid models.

This is precisely the problem: Toyota kept enhancing the hybrid drivetrain of the Prius, improving fuel economy with every new version. Now many different models, from the Toyota Aqua / Prius C to the Corolla Hybrid to the JPN Taxi basically all use the same family of engines, gearbox, battery, inverter and other electric systems. This has kept development costs low and maximized economic gain from the numerous patents that Toyota has received for the Prius.

Meanwhile, Tesla appeared on the scene as a complete outsider and took a radically different approach. By going for an all-electric drivetrain they don’t need an Atkinson-cycle internal combustion engine (ICE), an electrically controlled planetary gear transmission and many other mechanical parts that make the Prius family unique. They just need a bodyshell, an electric motor/generator, inverter and battery. For the first models the battery was basically built up from the exact same “18650” cells that power laptops and the bodyshell for the Tesla Roadster was bought in from Lotus.

Batteries for the automotive market are made by specialized suppliers such as Panasonic and LG instead of being based on in-house designs and intellectual property such as ICEs or gearboxes. Motor/generators and inverters are much simpler and less proprietary than ICEs. The basic technology for inverters used in BEVs and the electric part of hybrid drivetrains has been around since before the 1960s. Toyota engineers got the inspiration from the electrical systems used in bullet trains (shinkansen) that launched before the 1964 Tokyo Olympics.

If current owners of conventional or diesel cars replace their aging vehicles with hybrids then Toyota and its stable of Prius and cousins will do very well. If people however take a good look at the ecological realities of the 2020s and beyond, they will see that the sooner we can stop pumping more CO2 into the atmosphere, the less catastrophic our future will be on this planet. If we still drive cars, they will have to run on renewable energy sources, which hybrids can’t do (except plug-in hybrids for relatively short distances).

This raises a second issue: Toyota has been betting on hydrogen as the fuel of the future. Its Toyota Mirai runs on compressed hydrogen (H2), which is converted into electricity in an on-board fuel cell. This gives it a range of about 500 km between refuelling.

If Toyota were to sell BEVs with ranges of 300-450 km, this would undermine the rationale for hydrogen cars which need a completely new infrastructure for refuelling. Each H2 station costs millions of dollars and the fuel is expensive.

The most economical way of making hydrogen is from natural gas or coal, which releases greenhouse gases. Though one could make hydrogen through electrolysis (splitting water into hydrogen and oxygen using electricity), because of inefficiencies inherent in this process, this would actually consume about three times more renewable electricity than covering the same distance by charging/discharging a battery. This is why hydrogen will ultimately remain an automotive dead end.

What hydrogen technology basically gives Toyota is a political fig leaf: They can claim to have a path into a carbon-free future that does not rely on batteries (like Tesla and others). Using that fig leaf they think they can keep selling cars that burn gasoline, in California and elsewhere. Perhaps they can hold off moving beyond hybrids for years and years to come. If they can keep selling what they’ve got they may make healthy profits in the short term, but for the sake of the planet I hope this plan won’t work.

I’ve seen this movie before. In the 1990s Sony launched its MiniDisc (MD) player as a replacement for analog audio tapes and recordable alternative to digital Compact Discs (CDs). Then, in the late 1990s MP3 and flash memory came along: smaller, cheaper, more simple. The whole strategy fell apart. Sony could have accepted that MP3 was a superior solution, but that would have then put them on a level with every other audio consumer product maker. Their patents on MD would have become worthless. So they struggled on with trying to promote MD until they eventually had to kill it. From the inventor of the iconic Sony Walkman that had created a whole new market and sold the brand name to billions of consumers, Sony turned into a company that had lost its way. It let newcomers such as Apple with its iPod (which soon morphed into the iPhone) take over the market and consumer mindshare. The rest is history.

So if you’re listening, Toyota: Please build a car as spacious, practical and reliable as the Prius, but without a hybrid drivetrain that still releases CO2 with every km driven. Make it a no compromise battery electric vehicle. Support vehicle-to-grid technology, in which parked cars have an important role to play for stabilizing the electrical grid. Instead of working with fossil fuel companies to turn fossil fuel into hydrogen for thousands of yet to be built H2 filling stations, support expanding renewable power production from solar, offshore and onshore wind, geothermal and large scale storage, which is what we will need for a carbon-neutral future.

Meanwhile, when the time comes to replace my 12 year old car I will look at all the battery electric hatchbacks on the market then. If there is no Toyota amongst them then my next car will not be a Toyota. It’s as simple as that.

Huawei Nexus 6P Battery Upgrade

I’ve had my Huawei Nexus 6P for about two years now. The combination of a great camera, an excellent screen, good performance and decent battery life has made this my best smartphone ever.

However, a couple of months ago something happened as the battery capacity appeared to have collapsed dramatically. Sometimes the phone would shut down only 5 hours after I had disconnected it from the AC charger when I left home, starting off supposedly fully charged! I had to always carry a USB battery and cable with me to not risk losing the use of my phone in the middle of the day.

Attempts to recalibrate the capacity indicator helped only insofar as the phone would shut down at 14% charge instead of say 55% charge, so there was slightly more warning, but the number of hours was still too short. This actually seems to be a common problem with the Nexus 6P, which otherwise is still a great phone.

It’s not uncommon for Li-ion batteries to significantly lose capacity after about about three years, but if it happens after less than two years as in my case, that’s not very good. Fortunately, replacement batteries are available and any competent phone repair shop will be happy to do the necessary surgery to replace a battery that is on its way out. Unfortunately the days when you could simply pop open the phone case without any tools and swap the battery yourself are long gone. This is a trend started by Apple and almost every other phone maker has since followed suit. I think it’s meant to get people to buy a new phone sooner, which is good for Apple and its competitors, but bad for consumers and for the planet.

There are Youtube videos that will show you how you how to open the Nexus 6P case and disassemble the phone to swap the battery. This involves the use of a hairdryer or heat gun to soften the glue that holds it all together as well as a plastic card and a small screw driver. As I did not feel adventurous enough to attempt this myself, I contacted several phone repair shops here in Tokyo. Repair King Japan replied. Though they they didn’t have the Nexus 6P battery in stock they were happy to order one for me. Once they got it, I dropped the phone off and two hours later I could have it back with a new battery. So far it’s looking good: It’s been 40 hours since the last full charge (with battery saver mode inactive) and it’s still showing 64% with about 3 days of power left 🙂

UPDATE: At 72 hours, it still had 23% charge left. At that point I connected it to a charger.

Hopefully with the new battery my Nexus 6P will be a great phone again for a few more years!

Olympic Hydrogen Hype

Today’s Japan Times reports that the Organizing Committee of the 2020 Tokyo Olympics is considering the use of hydrogen torches to light the Olympic flame (“Olympic panel mulls high-tech hydrogen torch, pares soccer venues” — JT, 2017-02-27):

“An important theme of the Olympics is how to promote environmental sustainability. We will talk to experts and see how realistic it is in terms of technological development,” a committee member said.

One official said there are still safety and cost concerns, and asserted that there also was a need for a lightweight torch that can be easily carried.

In March 2016, the Tokyo Metropolitan Government announced a project to have the 6,000-unit athletes’ village for the games run entirely on hydrogen power.

The Japanese government is one of the most active promoters worldwide of a so called “hydrogen economy”. It sees the 2020 Olympics as an opportunity to showcase Japan’s lead on hydrogen. Other projects are the construction of a nationwide network of hydrogen filling stations for hydrogen fuel cell vehicles (HFCV) such as the Toyota Mirai, research into shipping liquefied hydrogen from overseas using special tankers and production of hydrogen from lignite (brown coal) in Australia for export to Japan.

Let’s start with the most obvious problem in the article, the hydrogen fueled torch: The usual Olympic torches use LPG (propane/butane) as a fuel, a gas mixture that can be stored as a liquid under moderate pressure at normal outdoor temperatures. This makes it easy to carry a significant amount of fuel in a light weight container. Hydrogen by contrast does not liquefy unless chilled to about -252 C. Hydrogen powered vehicles run on compressed hydrogen instead, at pressures of up to 700 bar, equivalent to half the weight of a car on each cm2 of tank surface. As you can imagine that kind of pressure calls for some fairly sturdy containers. An even bigger problem is that pure hydrogen flames are invisible because they radiate energy not as light but as UV. You could feel the heat, but you couldn’t directly see if the flame is burning or not, which makes it quite hazardous. Talk about playing with fire…

The comment about running the Olympic village on “hydrogen power” is quite misleading. It’s like saying they would run the Olympic village on battery power, without explaining where the energy to charge those batteries came from. Like batteries, hydrogen is not a primary energy source, it’s an energy carrier. Since elementary hydrogen does not exist in significant quantities on earth, it has to be produced using another energy source such as natural gas or electricity generated using coal, nuclear, wind or solar.

Though it’s possible to produce hydrogen from carbon-free energy sources such as solar electricity (splitting water through electrolysis) and then produce electricity from hydrogen again, this process is far less efficient than either consuming renewable electricity directly or via batteries. When you convert electric energy to chemical energy in hydrogen and back to electricity, about 3/4 of the energy is lost in the process. This is incredibly wasteful and far from green.

With its sponsorship of hydrogen, the Japanese government is trying to create business opportunities for industrial companies such as Kawasaki Heavy Industries, a Japanese shipbuilder (see “Kawasaki Heavy fighting for place in ‘hydrogen economy'” — Nikkei Asian Review, 2015-09-03) and for its oil and gas importers, as almost all hydrogen is currently made from imported liquefied natural gas (LNG). In the longer term, the government still has a vision of nuclear power (fission or fusion) producing the electricity needed to make hydrogen without carbon emissions. Thus the ‘hydrogen economy’ is meant to keep oil companies and electricity monopolies like TEPCO in business. The “hydrogen economy” is coal, oil and nuclear hidden under a coat of green paint.

These plans completely disregard the rapid progress being made in battery technologies which have already enabled electric cars with ranges of hundreds of km at lower costs than HFCVs and without the need for expensive new infrastructure.

Hydrogen, especially when it’s produced with carbon-intensive coal or dangerous nuclear, is not the future. Japan would be much better served by investing into a mix of wind, solar, geothermal and wave power, combined with battery storage and other technologies for matching up variable supply and demand.

See also:
Hydrogen Fuel Cell Cars Are Not The Future (2016-12-05)