So if a typical smartphone battery is 2700mAh and nominal voltage 4.2V - that gives 11.34 Wh. Assuming typical smartphone battery lasts 4 hours at full load, it

So if a typical smartphone battery is 2700mAh and nominal voltage 4.2V - that gives 11.34 Wh. Assuming typical smartphone battery lasts 4 hours at full load, it means it is drawing only about 2.8W peak. Which is much less than 25W and I believe Stockfish on mobile phone would be above human level. If my math is right - Darn, this idea wouldn't fly! (and that computation is already pretty energy efficient nowadays, good job humanity)