The shiny concepts on the Toyota and Lexus stands at this year’s Japan Mobility Show ranged from massive mono space luxury vehicles, to SUV crossovers and sleek coupe models, but they all had one thing in common – they were all battery-powered.
This wouldn’t be a surprise on any other manufacturer’s stand, but Toyota has, for decades, banged the drum for hydrogen power, pouring money and resources into fuelling its cars with the fuel cells. Successions of Krüger FCEV prototypes begat the Mirai, which, after the Honda Clarity (another company that has eschewed hydrogen for battery power) was the world’s most successful hydrogen saloon. Yet at a Toyota board level, the Mirai is now considered a failure.
The £63,500 Mirai has sold by the handful round the world and while there will be 500 on the streets of Paris during next year’s Olympics, this pioneering car has proved a financial disaster, barely recouping its costs let alone the towering cost of developing bespoke 700 bar hydrogen tanks, fuel cells and control systems.
No hydrogen success
Speaking at the show, Hiroki Nakajima, Toyota executive vice-president and chief technical officer, said that the Mirai hasn’t been a success at all. “We have already tried with the Mirai,” he says, “but unfortunately it has not been successful because of the hydrogen filling station point of view, there are few… So we have changed our strategy from passenger cars to commercials.”
The hydrogen industry initially described the introduction of hydrogen cars and trucks as being a “chicken-and-egg situation”. The chicken (refuelling infrastructure) was required as much as the eggs (fuel-cell vehicles) and both would have to be developed at the same time. They weren’t. Now the chicken has caused the demise of the egg.
Fuel-cell development will continue but Toyota now sees heavy haulage, marine, bus-and-coach and rail applications as a natural fit for the technology, though it retains a commitment to pickups and its hydrogen tie-in with BMW.
Nakajima says his fuel-cell packs will still be shaped and sized so they can be fitted to a passenger car should the need arise, and we were shown a series of shaped 10,000psi pressure tanks on which Toyota has been working. They are flat ones, which can be fitted in place of a battery in an electric vehicle, and saddle-shaped items, which sit either side of a propellor shaft in a rear drive car or pickup. Engineers say they are aiming at having just as long life as the current round items which, in Japan, is 15 years by law (though Toyota is pushing authorities to allow a longer life).
We also saw the prototypes of the latest third-generation fuel cell, which is now half the size of the previous unit that was the size of an airline carry-on case. It also has stainless steel separators instead of the old cell’s titanium ones, so it costs a lot less to manufacture. Overall, fuel-cell costs are said to be halved, with a 20 per cent greater cruising range (which means they’re more efficient) and a maintenance requirement reduced by 2.5 times.
New battery strategy
But at this year’s show, it was the battery strategy that Toyota was promoting. There’s a lot of ground to make up, as Toyota has lagged behind in battery technology for years, mistrusting lithium-ion chemistry and hoping the world would adopt its hybrid petrol-electric technology as an eco standard. Some might say that Toyota is entering the market just as its rivals are starting to question their headlong flight down the battery-electric route.
Nevertheless, Toyota claims that its new Gen-3 batteries will start to be introduced from 2026/2027 and will set new standards, giving longer driving range, faster charging and lower cost.
Lexus, the company’s luxury division will become an all-EV brand by 2030, while the Toyota marque will continue to offer a range of alternative drivetrain tech including hybrids and plug-in hybrids, but will be selling between 30 and 40 per cent EVs by 2030. Gazoo Racing will persevere with combustion engines but using CO2-free liquid fuels such as hydrogen and e-fuels.
This strategy will take Toyota EVs through into the next decade with three different battery technologies, including a claimed breakthrough in solid-state battery technology. Yet this summer, Koji Sato, Toyota’s chief executive admitted that the solid-state research wasn’t going well and that it might take longer than planned, so the new schedule for far-future introductions might prove as accurate as forecasting next year’s weather.
In the here and now, however, the reduction in battery height with cells just 100mm high and power take-off on the side rather than top is a key part of the new architecture, as it allows the new generation of EVs to be lower with more wind-cheating shapes. Toyota works with Panasonic on its cell design but is, along with BYD, one of the few car makers to build its own battery cells. These proposed new cells, which are fitted into the Toyota and Lexus concept models at the Japan Mobility Show, will go into production in a new factory in 2026.
The cells will be fitted to 1.7 million of the 3.5 million annual battery electric vehicles (BEVs) that Toyota expects to sell globally by 2030. As well as improving the ruggedness and serviceability of the cells – EVs are often scrapped after quite minor bumps for fears of internal short circuits, which raises the cost of insurance –there are also savings in the manufacturing of cells, which can be expensive and time-consuming to produce.
Evolution not revolution
Like Rolls-Royce, Toyota tends to improve what is already there and so it proves with batteries. The first ‘Performance’ battery slated for 2026/7 will use tweaked lithium-ion chemistry with more nickel in the nickel manganese cobalt (NMC) cathode material and tweaked electrolyte to increase the range to around 497 miles. It will also allow a 20-minute fast charge capability from 10 to 80 per cent, and a 20 per cent reduction in cost compared with Toyota’s current battery model, the bZ4x.
The ‘Popularisation’ battery will be Toyota’s lithium-iron-phosphate (LFP) chemistry. LFP is a cheaper and more robust technology favoured by Chinese car and battery makers, such as BYD and Catl, but it has the drawback of not being as energy dense as lithium-ion so has previously been the choice of bus and coach applications where there’s more room to put them. More recent developments, however, have seen them used with success in battery passenger cars. Toyota’s version will cost 40 per cent less than the cells in the bZ4x and will have a fast charging time of 30 minutes for a 10 to 80 per cent charge.
There’s also a ‘High Performance’ battery, which is based on lithium-ion NMC chemistry, but with even greater nickel content in the cathodes and bipolar construction. Driving range projection for this new battery is 621 miles, with a 10 per cent reduction in cost compared with the Performance battery and a 20-minute 10 to 80 per cent fast charging time. They are expected on the market by 2027 and 2028, though the cost claims are highly dependent on volatile raw materials markets, and nickel-enriching cathodes can be a risky business as the metal is less thermally stable than the cobalt it replaces and burns at a very high temperature.
Asked about this, Nakajima said that Toyota’s batteries have different and inherently safer “internal arrangements” to other cells and that he will offset some of the cost savings into extra battery safety. “The most important thing is how we keep it [the new battery chemistry] secure. Safety is the most important consideration and if we find we can’t secure safety,” he said, “we won’t do it’’.
The fourth chemistry is solid-state; an auto industry holy grail, where the ions in each cell move through a solid medium rather than the less stable liquid electrolyte of current vehicle battery technologies. Advantages here are stability and faster charging, but there are still issues with solid-state batteries’ safety and longevity. The former issue is with dendrites, which grow out of the cathode like calcium stalagmites and threaten to pierce separators and cause a short circuit and fire. Toyota engineers say this problem affects all batteries and they have solved it. The short life issue, though, is still a work in progress and Toyota says it has a laboratory solution but is working on scaling it up for mass production.
The claims are that solid-state battery tech will be ready in 2028 with a driving range of 621 miles, and fast charging in 10 minutes for a 10 to 80 per cent charge, but there’s no cost projection.
So, that’s it…
Fuel-cell cars once formed part of a utopian wider hydrogen future. It seemed such an elegant solution, with beautifully simple engineering (water to water, and the same machine used to create electricity and then used in reverse to create the hydrogen). Sure, it wasn’t as efficient as battery electric, but that sort of missed the point that if you generated electricity using sun or wind, there might be times you couldn’t use the electricity created and hydrogen could be used as an energy buffer. That problem still remains, as does saving carbon dioxide to assuage climate change and global temperature rises.
Still, it was all good while it lasted, though I can’t help quoting Beth Dawson, of Fuel Cell Systems, on the subject of saving hydrogen refuelling for certain types of users: “Once you’ve got the hydrogen there, you can do clever things with it.”