Pocket Reform charging question

I understand that Pocket uses USB-C charging, and one of the fancy high-power modes.

Is it capable of charging, at obviously a (much) lower rate, from say average 2A, 3A 5V USB-C chargers? I’m buying the 60W charger and cable from Crowd Supply; I’m thinking of how I might fare while away from home and charger.

Assuming Pocket Reform is powered off, do y’all think I might get an overnight charge from a 2 ampere 5V charger?

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In theory, yes, but in practice it is not ideal and needs some firmware improvement (system controller FW). The current state machine wants at least 6V charging voltage and otherwise ends up in an on-off loop (with a few seconds in each state) trying to renegotiate charging.

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I’m aware it may have been answered elsewhere, but are there recommended chargers that work well?

RAVPower, Ugreen, Apple, PinePower appear to work fine.

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Thank you, got it. Not surprising, it’s a difficult problem.

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I’m also seeing weird charging problems on my Pocket Reform.

From the factory the battery showed 29% and barely moved anywhere when charging, max I got was 31%. Then following another thread here that mentioned a callibration issue, I just ran it empty, and now it indeed charges higher, but still doesn’t pass ~80% on full charge.

Using an Anker 735 GaN charger (65W).

Any suggestions? Should I drain it again?

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I had a similar sort of experience, but after a couple of “discharge 'til dead” cycles it now shows charging to 100%. I’m using the UGreen Uno GaN 65w Nexode Robot charger.

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Mine charged till 100% once I did like 3-5 empty/full cycles.

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I suspect it’s indeed a calibration issue where the battery charge and number displayed aren’t aligned. It seems the batteries are charged fully, but the displayed charge percentage gets stuck at some point.

What makes me say that is that I booted my Pocket Reform when it was at 17 % earlier today. It went all the way down to 1 %, and has been displaying that value for about 30 minutes now without giving in to emptied batteries.

It’s probably the ModelGauge algorithm in the battery monitor chip that first needs to learn the lower and upper charge limits. Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/max17320.pdf

Thanks for that pointer. It says there (p. 62):

To determine the true accuracy of a fuel gauge, as experienced by end-users, the battery should be exercised in a dynamic manner. The end-user accuracy cannot be understood with only simple cycles. To challenge a correction-based fuel gauge, such as a coulomb counter, test the battery with partial loading sessions. For example, a typical user may operate the device for 10 minutes and then stop use for an hour or more.

That sounds interesting; I’ll use the charger accordingly. (So far, I’ve always kept the charger plugged in for hours, making sure it gets full.)

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