nPM1100 doesnt start charging empty battery

RE: nPM1100 doesnt start charging empty battery

Jekin — Tue, 22 Oct 2024 07:49:23 GMT

Thanks. I was thinking already about the exact same solution. I'll test that.

RE: nPM1100 doesnt start charging empty battery

Priyanka — Tue, 22 Oct 2024 07:45:58 GMT

Hi Eugene,

We do not have any schematics etc for the pre-charging circuit that we can share, but maybe you can overcome this issue by placing a diode and a serial resistor from VSYS to the VBAT pin in parallel with the nPM1100 to slightly and slowly charge the battery when it is too low.

Hope this helps.

-Priyanka

RE: nPM1100 doesnt start charging empty battery

Jekin — Mon, 21 Oct 2024 08:29:03 GMT

Hi Priyanka,

Any news on this?

Best regards,

Eugene

RE: nPM1100 doesnt start charging empty battery

Priyanka — Fri, 11 Oct 2024 13:08:48 GMT

Hi Eugene,

I am not sure regarding whether we have any reference for the pre-charging circuit. I will check internally and get back to you.

Regards,

Priyanka

RE: nPM1100 doesnt start charging empty battery

Jekin — Thu, 10 Oct 2024 13:58:21 GMT

Hi Priyanka,

Thanks for your reply.

This case is quite common, any lithium-ion/polymer battery may have voltage below 2.1V when deeply discharged.

After learning the datasheet I can't find any information about pre-charging, also reference circuits haven't it.

Does Nordic has any reference circuit for the nPM1100 showing the required pre-charging module implementation? Adding extra components connected to VBAT and sinking current into this pin may break the nPM1100 battery detection algorithm and also the charging algorithm too.

Best regards,

Eugene

RE: nPM1100 doesnt start charging empty battery

Priyanka — Thu, 10 Oct 2024 13:14:17 GMT

Hi Eugene,

The nPM1100 has automatic trickle charging which allows to bring the battery charge to a certain limit before fast charging. But there is a required minimum charge for the battery below which it can show an error:

This might be the reason that you have an error since 1.09V is below the required 2.1V. You could likely try pre-charging the battery maybe.

Regards,

Priyanka

RE: nPM1100 doesnt start charging empty battery

Jekin — Thu, 10 Oct 2024 08:40:39 GMT

Here is specification of the PCM module. Release voltage to restore circuit after triggered over discharge protection is 3.5V: