TOKYO — In a world where lithium ion power packs are the norm and buzz is building around solid-state batteries, old nickel-metal hydride batteries seem like yesterday's news.
After all, Toyota has been using the chemistry since the 1997 launch of the Prius hybrid.
But engineers at Toyota have found a way to squeeze more juice out of the old tried-and-true battery technology, and it is giving Toyota's latest hybrids a new life in the electric vehicle age.
Toyota calls its innovation the bipolar nickel-metal hydride battery. A new structural design delivers not only a more powerful battery, but one that is much more compact — essentially doubling its power density while using the same basic chemistry.
Toyota deployed the new battery this year in the redesigned compact Prius C hybrid. Each cell delivers 1.5 times the output of the old setup, and the structure allows for 1.4 times as many cells in the same space.
"If we use the same space, we are able to fit a battery that has twice the output," said Motoyoshi Okumura, group manager of Toyota's advanced battery development division. His team started working on the new battery architecture in 2016 and expects to ramp up deployment.
The innovation is helping Toyota keep hybrid vehicles relevant, competitive and affordable as much of the industry splurges on lithium ion battery capacity for full-electric vehicles. Toyota aims to sell 8 million electrified vehicles in 2030. But only 2 million of those will be EVs or fuel cell vehicles; some 6 million vehicles will be traditional hybrids and plug-ins.
For context, Toyota sells only about 2 million hybrids a year today.
To power those vehicles, Toyota is investingin battery development through 2030, to secure 200 gigawatt-hours of battery supply by the end of the decade.
Toyota will keep using the traditional nickel-metal hydride batteries, but it will increasingly ramp up deployment of the bipolar version as the automaker adds new models through 2030. "We will look more proactively to adopt this new battery," Okumura said.