[KennyBlanken]

Battery progress was in some ways slowed but also accelerated by oil companies who kept buying up patents on solar and battery stuff that looked promising, and then sat on the patents, refusing to license it.

One oil company bought Cobasys, which owned all the NiMH patents. Thereafter, Cobasys refused to license NiMH batteries to anyone making a vehicle, except large ones like transit busses. Several early EVs used NiMH batteries until Cobasys was acquired and set up the restrictions.

This really lit a fire under researchers and battery industry to try and improve lithium ion, which had hit the market in the early 90's. Once the price of Lithium Ion started falling, the market very quickly forgot about NiMH batteries. In about ten years prices have fallen to one fifth of what they were. That fall has slowed, but it's still dropping.