External battery for HP Prime?

[math7]

Thanks for the answers, I'll try it with some fear, I hope that nothing bad happens that damages the calculator, the battery that I own the buy it in a very famous online store.
The battery I'm talking about is this

Battery external

I think it is useful to know this because when loading the Prime with the factory charger because it is possible that we forget and leave it connected more time than necessary to reach 100% and leave it 8 hours or more can be damaged little by little the battery Internal, while using an intelligent external battery, these batteries are disconnected as grsbanks says, so that at the time that no charge is detected is automatically disconnected even after 10 hours the external battery will turn off and will not supply more charge.