The battery capacity in milliamp hours (mAh) gives you an indication of how long it will keep your Touch Board project alive before a recharge. With the Touch Board powered by a battery and running the Touch Mp3 code it consumes roughly 70mA and while it plays a track it consumes about 100mA. A quick calculation would be to see how many times you can fit 100mA into the capacity rating. So if you bought a 1000mAh single cell LiPo battery it should be able to run for 10 hours at 100mA (1000mAh/100mA = 10h). We recommend getting a battery at least over 400mAh.
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