Toyota, in collaboration with Idemitsu Kosan, has decided to create a supply chain for the mass production of solid-state batteries. The foundations for commencing mass production are set for the 2027/2028 period.

The world’s largest car manufacturer has confirmed that it has been working on basic technologies for these batteries since 2006, while the energy company Idemitsu Kosan has been involved in this endeavor since 2001. The joint research and development’s objective is the use of solid sulfur electrolytes, which has become the primary avenue of research.

A promising material for use in solid-state batteries, in comparison to other components, they are relatively soft and malleable, making them easier to process, thus making them ideal for mass production.

A working group aims to promote joint development and has designed a plan that will be implemented in three phases. The first part is to develop solid sulfur electrolytes and prepare a pilot plant. Next, mass production will commence in the pilot plant. In the third phase, production scaling to larger scales will be addressed based on the results from the previous phase.

To achieve this, Idemitsu Kosan has developed a series of lithium sulfide production technologies, an intermediary for solid-state electrolytes, using, among other things, by-products from petroleum processing.

A solid-state electrolyte is considered a safer technology that, with mass production, could even be more cost-effective. It may offer higher power outputs than liquid electrolyte storage systems, opening doors to more intensive applications, such as aviation.

The goal is to improve the lifespan, the primary challenge for the many laboratories working on this configuration, which has become a focal point for developing advanced batteries.

One of the keys, in addition to improving energy density, is that Toyota has managed to simplify the production process of the materials used to manufacture these batteries, describing the discovery as a significant advancement that could drastically reduce charging times and increase range.

The Japanese company has developed processes to offer packs with over 745 miles of range to an average car, with a charging time of 10 minutes or less, and using cells that will use fewer materials and be cheaper than lithium batteries.

But while its development is ongoing, Toyota will opt for a diversification strategy, adopting different battery chemistries and suppliers for its range of electric cars. This means that the Japanese manufacturer will rely on up to four battery chemistries for its cars, including both liquid and solid-state electrolytes.