It is possible to build safe batteries, and someone, someday will develop and build these at an affordable price. It is also absolutely essential, because this is the key to propelling cars using solar, wind, and tidal power.
During WWII the Japanese cut the West off from the rubber supply, and the US government started a crash program to develop synthetic rubber. When the formula was discovered, the inventors were paid, but it was RELEASED PATENT-FREE to everyone to use, because the war was far more important than profit for the few.
This is where we stand today, and this is what we should do now.
There is no problem with paying the actual inventors: after the first twenty million or so, every possible desire and need will be met. No reason to enrich corporations for twenty years just because they hired this or that guy.
Xerox copies cost 25¢ for years, until the patents ran out. After that quality improved and the price plummeted.