In fact, the de facto upper limit for laptop batteries is 100 watt hours since this is the largest battery size permitted on a flight by the FAA (the US air tra

In fact, the de facto upper limit for laptop batteries is 100 watt hours since this is the largest battery size permitted on a flight by the FAA (the US air travel regulatory body) without special approval [1]. The CPU would drain such a battery in 1 hour and 50 minutes. [1]: https://www.tsa.gov/travel/security-screening/whatcanibring/items/lithium-batteries-more-100-watt-hours https://www.tsa.gov/travel/security-screening/whatcanibring/...