External battery charger for Librem5

librem5 · March 20, 2022, 10:00pm

Yes already discussing it with support.
Expecting reply tomorrow or so about further steps.

librem5 · March 22, 2022, 4:53pm

Got the RMA, I’ll update the post once I get phone back.

guru · March 24, 2022, 6:43am

I own an additional battery, an universal charger and I charged it with this external charger (specs are visible below). The battery shows now 4.303V. As I read in this and other threads:

I should not insert the battery with this voltage. correct?
What should a resistor has as Ohm (Ω) to discharge the battery externally before inserting?

UPDATE: IIRC my electronic school, a battery of 4500mAh and 4V which will be discharged in 9h means that this is done with: 4500mAh / 9h = 500mA = 0.5A and following R = U / I means: 4V / 0.5A = 8Ω. A I wrong?

Thanks.

fsflover · March 24, 2022, 12:01pm

Charging Librem 5 Batteries Outside of Phone

It doesn’t matter whether it’s charged externally or internally. The battery is fine with 4.35V, but you shouldn’t put a battery charged above 4.2V into the phone at all. The internal charger is already configured to not go above 4.2V, while when charging externally it’s up to you to ensure that it doesn’t go above 4.2V.

If you do happen to charge it above 4.2V, you should discharge it a bit before putting into the phone so it won’t provide voltage higher than 4.2V to the phone.

(as already noted somewhere else, the phone should actually be fine with 4.35V, but IIRC one of the M.2 cards is not; plus I haven’t checked the whole power path to be sure that there are no other components that won’t like voltages above 4.2V, so can’t do any claims about that either)

Post can’t be empty

dos · March 24, 2022, 1:45pm

You can insert it, just keep the modem and GPS off until it goes below 4.2V (POWER_SUPPLY_VOLTAGE_OCV).

librem5 · April 14, 2022, 6:24am

Just received my phone with motherboard replacement .
I’ll update the thread by next week (or earlier if I hit issue).

librem5 · April 15, 2022, 10:15pm

I can enter jumpdrive, I don’t have need to flash right now so not trying flash at moment.

RelativeToZero · May 18, 2024, 8:54pm

Trying to bring things back on topic, I have been looking for one of those charging stations like the ones for recharging sets of 2-way radios to charge up 2-4 spare Librem5 batteries at once. My reason is that I still want to figure out a way to stop bringing android/ios with me when I go on backpacking trips. Plus, I think just having a small pouch like those USB drive carrying cases with a few extra batteries in it would be easier and less bulky than an external battery pack.

librem5 · May 18, 2024, 10:54pm

4 spare batteries would be 16000 mah + kinda big charging station, I think at that point one or 2 10000 mah external packs would be more convenient and lighter.

Lliure · May 19, 2024, 6:00pm

I’ve been carrying both pretty much wherever I go for the last six months: one spare L5 battery and one 20,000 mAh power bank.

I almost always end up using the latter. Not having to power down the phone and then boot up again is just too convenient.

In two scenarios, I still find the spare battery useful: when traveling light, e.g. at concerts, and at venues where bringing power banks is forbidden, e.g. at the stadium.

veleno · July 12, 2024, 7:44pm

Please Could you let me know how did you insert the battery to recharge it?
I bought it on Amazon reading your post but battery is larger than the max opening of the charger! I can’t insert it!
In fact, if you measure battery it’s 6mm instead the max opening of the charger is 55mm!
Thank you

librem5 · July 12, 2024, 8:38pm

Even bigger battery than that of Librem5 can fit in this charger.
Bottom / side part is spring loaded, you need to pull it back before battery can slide in.
Contacts can be moved around.
Please see pictures in this post: External battery charger for Librem5 - #77 by librem5

I can take a video if you want to see how it works.