Category Archives: Tesla

Toyota Hydrogen Combustion Engine Cars

Posted on by
Reply

Since 2014 Toyota has sold a little over 10,000 Toyota Mirai, a hydrogen fuel cell vehicle (FCV). The starting price of this 4 seat sedan model in Japan is about 7.1 million yen (currently about US$63,000) which is more than 50% more expensive than a battery electric Tesla Model 3 which seats 5 adults. And it seems unlikely that Toyota can make a profit on a car being made in such small numbers as the Mirai, unlike Tesla does with the cars it makes in large numbers in its plants on three continents.

Tesla sold about half a million battery electric vehicles (BEVs) last year and looks set to sell somewhere between 900,000 and 1 million cars in 2021. This means Tesla will have sold twice as many BEVs every week in 2021 than the total number of FCVs Toyota has sold since 2014. The sales gap between BEVs and FCVs is getting bigger and bigger.

Recognizing that the high cost of fuel cells makes it difficult to compete, Toyota has announced that it sees a market for cars with internal combustion engines (ICE) that burn hydrogen instead of gasoline. They should be cheaper to make than fuel cell cars and will not produce any CO2 if hydrogen is made from non-fossil energy sources.

It’s not a novel idea though. BMW tried it in its BMW Hydrogen 7 technology carrier based on its 7-series back in 2005-2007. It never went anywhere. Besides the absence of a fuel supply network, there were also issues with emissions. Hydrogen flames burn extremely hot, which means you end up with a lot of smog-forming NOX emissions — worse than diesels.

In terms of efficiency, hydrogen ICEs are worse than FCVs which are much worse than BEVs. While BMW used cryogenic tanks with liquefied hydrogen at -253 °C, Toyota most likely will use high pressure tanks like in its Mirai for its hydrogen ICEs. They hold hydrogen gas at pressures of up to 700 bar. Both liquefaction and compression require huge amounts of electricity that can not be used for propulsion but is effectively wasted. An FCV consumes three times more electricity for electrolysis to make the hydrogen fuel it consumes than a BEV uses to charge a battery to drive the same distance. A hydrogen combustion engine is even less efficient. Where will this hydrogen come from? We don’t currently have a surplus of solar panels or wind turbines to produce this electricity. That means a hydrogen economy will need significantly larger investments in renewable energy than with battery vehicles. Hydrogen for cars makes no economic sense whatsoever.

It makes even less sense for hydrogen ICEs than for hydrogen FCVs. Fundamentally, it’s no more than an excuse for not giving up on building internal combustion engines, pretending that nothing has changed even in a world that is facing climate change that we need to address as soon as possible.

I am afraid Toyota will not make a turn-around and face the reality that the industry is switching to BEVs within the shortest time possible until it replaces Toyoda Akio, its current company president. Mr Toyoda is the grandson of the founder of the company and a keen race car driver. He lacks the vision that Toyota will need in the transition to a carbon free future. Mr Toyoda needs to retire, along with the dead-end technologies he is committed to.

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

Posted on by
Reply

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

Posted on by
Reply

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.

Test-driving a Tesla Model 3 in Tokyo

Posted on by
Reply

Recently my son Shintaro and I went to the Tesla showroom in Aoyama, Tokyo to take a Tesla Model 3 for a test drive. I wanted to see for myself how this electric vehicle compared to my almost 12 year old Prius hybrid and to be able to compare it to future EVs from other brands that we may eventually consider.

I’d noticed an increasing number of Teslas around Tokyo, though they’re still far rarer than around the San Francisco bay area. Given that much of Japan is densely populated, range anxiety (an often cited reason for slow electrification) should be less of an issue here compared to the US, particularly with cars that already have over 400 km of range.

I love the practicality of the rear hatch of my Prius that allows me to carry two road bikes without disassembly by simply folding the rear seats. The Tesla Model 3 has a much less accessible trunk, which pretty much rules it out for me. The Model Y will be more practical, but is also even bigger. Apparently it won’t be available in Japan until a year or two after it starts shipping in the US this month (March 2020).

Tesla’s models are quite large by Japanese standards, with implications for parking and for driving on narrow back streets. For example, these are the dimensions of the Tesla Model 3 vs. the current generation Toyota Prius (XW50):

Length: 4690 / 4570 (+120 mm)
Width: 1850 / 1760 (+90 mm)
Height: 1440 / 1470 (-30 mm)

Exact numbers for the Model Y aren’t available yet, but it’s expected to be about the same width but about 1600 mm tall (160 mm taller than the Prius).

The test drive was an unusual experience by Japanese standards. Somebody had mentioned that the dealer experience with Tesla is more like visiting an Apple store than a traditional dealer showroom. I’d say the difference was even greater.

Customer service expectations in Japan are incredibly high and that is probably one factor for Tesla’s relatively sluggish sales here, see a recent Japan Times article.

Shintaro had tried to make the reservation online and was promised a callback within 48 hours, but that never happened so he had to call again to fix up an appointment.

Even when I take my Prius to an oil change at a local gas station, I’ll be served a cup of coffee while I wait. By contrast, when we visited the Tesla showroom to evaluate a JPY 5,100,000 (USD 48,000) car, all we received was a business card of the sales person. They don’t even give you paper brochures. You can look it all up on the website, right?

Before the test drive they took photo copies of our drivers licenses. We were instructed not to take any pictures and to follow the rules of the road. We would be liable for any incidental damage to the car during the test drive. Then we got into the car parked by the roadside outside the showroom, first as passengers, then later taking turns driving it around Akasaka.

I liked the seats, which were nice and firm. The acceleration when you put your foot down is amazing. It feels like a big car but with enough power for its weight. Getting back into the Prius later, it felt quite light by comparison, by which I don’t mean acceleration but it simply feels like a lot less metal being moved around. It tips the scales at about 280 kg less than the base Model 3 (1335 kg vs. 1612 kg).

Some of the controls took some getting used to, such as the lever action of the indicator stalk (which is on the left unlike in Japanese cars) or putting the car into park or into drive with the right stalk. Much of the demonstration involved showing the use of the center screen and its user interface. Many of the functions of the car, such as the electrically assisted steering or the regenerative breaking can be tweaked there, to change the feel of the car.

Headroom in the Tesla was good but personally I don’t much care for the glass roof. In a roll-over accident I would feel safer with a steel roof, but maybe those are not so likely with the low center of gravity afforded by the floor-based battery. The car interior felt overheated when we got into it and no fan was blowing, but I only asked about fan control towards the end of my driving portion. In any other car I would have easily figured it out on my own.

Checking out the trunk and the “frunk” (front trunk) after we got out of the car, the limited access for bulky luggage from the rear was quite a contrast to our Prius, in which we regularly move large items from a DIY center or bicycles for cycling tours far from Tokyo. The Model Y will address that, but it’s also 160 mm taller than the Prius on top of being 90 mm wider like the Model 3. That’s more air resistance and more kWh used to overcome it. That’s one thing I love about the Prius, it offers all this interior space despite being compact and efficient on the outside. 🙂

The width would already make a Model 3 or Model Y a very tight fit in our driveway. We would also have to figure out if there’s enough clearance around the car to plug in the charging cable for overnight charging.

In summary, Tesla’s range of cars is not an easy sell for me as a Japanese customer. While they have great technology, some of the design choices are not a good fit for Japan and the customer experience when dealing with the company (especially given the price range) will not match a lot of cultural expectations.

UPDATE (2020-03-19):

Size information has finally been released for the Model Y. These are the exterior dimensions compared to my current Prius:

Length: 4751 / 4570 (+181 mm)
Width: 1921 / 1760 (+161 mm)
Height: 1624 / 1470 (+154 mm)

Given the width and height it looks like it has roughly 20% more frontal area than the Prius which will impact its air resistance and hence energy usage at freeway speeds.

Toyota is yielding the future to Tesla and other EV makers

Posted on by
Reply

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.