battery low alert

hi,
my pb turns itself off at10% battery life without the low battery notification.

I know there is because the other pb I had did that. Does anyone know how to turn it on? Thanks for your help.

Try doing a drain test and there's a chance that within one or two recharge cycles following that, it will have improved.

The reason it's happening is because the battery level indicator is miscalibrated, so it's reaching the minimum voltage (3.4V) while it still thinks it should have 10% of the energy left. The drain test may help it sort that out. No guarantees...