How about a nuclear battery, aka radioisotope thermoelectric generator (RTG)? This would be sealed in (carefully!) and would last the lifetime of the device, with no need for charging, ever. Would need special steps/handling to ensure safe disposal at end of product life, however.
How about a nuclear battery, aka radioisotope thermoelectric generator (RTG)? This would be sealed in (carefully!) and would last the lifetime of the device, with no need for charging, ever. Would need special steps/handling to ensure safe disposal at end of product life, however.