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February 3[edit]

Why do power percentage in Bluetooth devices always show in multiples of 10?[edit]

In my mobile and laptop, power percentage of my Bluetooth headphones always starts with 100%, 90%, 80%.....so on.

Why do power percentage in Bluetooth devices always show in multiples of 10? Rizosome (talk) 13:43, 3 February 2021 (UTC)[reply]

Likely because they don't need to be polled much. See the specification document here, (Battery Service, v1.0) under the heading "3.1 - BATTERY LEVEL".

For many devices, the battery level value will not change frequently; therefore it is recommended not to poll this characteristic value at a high frequency

Some devices do send 1% intervals, others 5%, 10%, or anything else. The specification says nothing about what levels they must poll at. WhoAteMyButter (📨│📝) 21:04, 3 February 2021 (UTC)[reply]

I don't know much about the specifics of Bluetooth, but I can provide an educated guess. A major chipset vendor likely only supports reporting battery status in 10% increments. Jdphenix (talk) 21:56, 3 February 2021 (UTC)[reply]

Another issue is that battery voltage can go slightly up when air temperature changes - too hot or too cold and the chemical reaction in the battery slows down and resistance of wires changes. The more digits the measurement shows the more often this would show up, and people would complain that the device is broken.

Also, due to internal resistance in a battery, its voltage changes as current draw changes. A second digit would jump up and down between quieter and louder bits in music. 85.76.65.17 (talk) 14:13, 6 February 2021 (UTC)[reply]