TOKYO MOTOR SHOW: Solid-state battery EV coming from Toyota in 2025

Toyota is on the cusp of a breakthrough with solid-state battery technology, which is widely acknowledged to be a game-changer for EVs and the automotive industry.

In a Q&A session on the eve of today’s Toyko motor show, Toyota's R&D chief and executive vice-president Shigeki Terashi confirmed that the company is on track to deliver next-gen solid-state battery tech to customers by 2025.

"We are developing solid-state batteries … aiming to make a fundamental breakthrough for charging and size," said Terashi-san.

The best lithium-ion battery cells still require significant recharging times and their density means the batteries either need to be large and heavy or lack range.

Solid-state batteries will remove these barriers by recharging in minutes, not hours, and offering improved energy density, lighter weight and significantly increased cruising ranges for electric vehicles.

As Toyota attempts to shift its image from car-maker to mobility company, it plans on showcasing its solid-state battery tech (developed in conjunction with technology partner Panasonic) in a special version of the Toyota e-Palette autonomous minibus, which will ferry athletes around the Olympic village in July 2020.

"At the time of the [2020] Tokyo Olympics we would like to produce a car with Toyota’s own solid-state battery and perhaps middle of 2020s we come up with the production model of the solid-state battery," stated Terashi-san.

Terashi said solid-state battery tech promises to revolutionise the automotive industry (and potentially give Toyota a leg up where it's been lagging behind other brands in the EV space).

"The advantage of solid-state battery is that it's strong against heat so it can be made compact. So you can create more capacity and … rapid recharge degradation will not happen quickly," said Toyota's R&D boss.

Toyota has only just revealed its first EV, the originally-named Ultra Compact Battery Electric Vehicle, or BEV for short, which will go on sale in Japan in 2020. It marks the first of many EVs to come from the Japanese giant, in a reversal of the policy that has seen the brand hitherto focus entirely on hybrids and hydrogen fuel-cell electric vehicles (FCEVs).

Terashi-san said the Japanese car brand will ramp up its lithium-ion battery production first, before commercialisation of solid-state battery tech follows in about five years. But it won't be cheap.

"Battery factory production process is very long. Even lithium-ion [battery] is huge. If you shift from lithium to solid-state, it will be very difficult to achieve that all at once. So, for the time being lithium-ion is being improved. Then for solid-state, that time will be between 2020 and 2030."

While the oddball Toyota e-Palette will be the first vehicle to get the next-generation solid-state battery pack, Terashi hinted the game-changing energy storage solution will slot into other models.

"The e-Palette is one candidate. We are considering other possibilities as well. I am advocating the use of the e-Palette for the solid-state batteries [for now]," he said.

Compared to lithium-ion batteries, which use liquid electrolytes usually in the form of a gel or paste, solid-state batteries use solid electrolytes which gives them improved thermal properties (they don’t get as hot).

Think of your mobile phone when you're streaming video or recharging – it gets pretty hot. Car batteries can get even hotter, and sometimes catch on fire.

Solid-state batteries allow for faster charge times, lower weight and higher energy density, which could allow for EV cruising ranges of up to 1000km with similar size/weight batteries used today.

But they’re hugely expensive, due to the complexity and time required to manufacture them. Nevertheless, Toyota's chief technology officer is adamant the tech is coming soon.

"Eco cars must be widely adopted," he insisted. "Laws and incentives can help drive markets but ultimately it's up to the customer. We have to deliver attractive electrified vehicles."