General • Official Documentation not clear on RTC backup battery ?

Hi,

I am referring to the https://www.raspberrypi.com/documentati ... p-battery part.

The warning is :

"We do not recommend using a primary lithium cell for the RTC, as it has a trickle charge circuit which is disabled by default. If enabled, this will kill the cell quickly.

But as stated in the documentation the

official battery part is a rechargeable lithium manganese coin

, which after some research ( cf https://industrial.panasonic.com/ww/pro ... els/ML2020 where you can see the ML2020 is in the "Secondary Batteries (Rechargeable Batteries)" category ) is a secondary lithium cell so the warning above does not apply to the official battery (they could make this clearer btw).

So far so good, one would think they can proceed with https://www.raspberrypi.com/documentati ... e-charging in confidence.

But looking at the specs of this ML 2020 directly on Panasonic reference https://industrial.panasonic.com/cdbs/w ... 000C18.pdf they explicitly say

Under no circumstances trickle charging should be used

That is very confusing : who is right, the raspberry pi documentation or Panasonic ? Something I am missing ?

Thank you,

Statistics: Posted by hqcamuser — Tue Jan 16, 2024 1:30 pm

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