In the early 2000s Chevron bought up the patent rights for NiMH batteries and refused to grant licenses for large batteries. Toyota was sued for patent infringement for their 90s RAV4EV and settled with Chevron.

Supposedly Tesla's early cars used off the shelf lithium ion laptop battery cells to get around these patent issues.

https://en.wikipedia.org/wiki/Patent_encumbrance_of_large_au...