Purism Librem 14 USB-C Power Delivery

I have a question regarding USB-C power on my Librem 14, please correct me if I’m wrong but I think the L14 can take 65 watts via the power supply. I have an Anker 737 power bank (PowerCore 24K) with up to 140 watts of output power. This power bank also has an integrated power output display. It shows a power draw of 20 watts and my power info applet on QubesOS always jumps from charging to not charging. Why does the power bank only deliver 20 watts even though it can charge a modern MacBook Pro 16?

It seems the L14 does not support Power Delivery 3.1.

Is that correct? Can that be fixed by software/firmware?

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For there used combo this can be fixed with particular (additional) PD3.0 100W hardware (USB Type-C Converter). In addition (for example), for DC power 5.5×2.1mm input, you would need to get 20V/5A WITRN PDC003 cable with E-marker (or other similar one).

In simple words (explanation) you are not getting pure PD negotiation (source=>sink) form Anker 737 Power Bank (PowerCore 24K). Thanks for sharing this info here!

To me (and to be slightly more precise) it looks like that the L14 does not support QC5 charging protocol. USB-C1 and USB-C2 are identical in their output specs (the built-in three-channel Nanxin Technology SC8815 is used for three-channel output voltage conversion and the two protocol chips use Infineon CYPD3171): AFC, QC5, PD3.1, PPS. In short, this 140W 2C1A power bank is probably (if not certainly) missing USB-IF certification. YouTube link (great teardown or this Anker power bank) is here.

Just small demonstration of what I wrote/linked above about AFC, QC5 power negotiations by using quite similar power source as here introduced Anker power bank:

Additional picture with another, but dedicated USB-PD power supply (PD3.0 showing both D+ and D− at 1.81) and charging very same laptop battery that is charged now at more than 80%:

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Crazy support! Thanks Quarnero! I am not as tech savvy as you. Would my Anker power bank work with the mentioned 100W USB-C converter + cable?

For me convenience is important. Do you know a power bank that would work out of the box with the L14? Preferable Anker.


20V USB-PD output I found (I’m not expert either) here:

  1. RAVpower RP-PB058 26800mAh PD,
  2. Zendure A6PD 20100mAh 45W PD −− if you find one,
  3. ANKER PowerCore III Elite 25600mAh 60W (20V/3A in/out) PD A1290 −− SC8812A charger controller with I2C interface, etc. might charge out of the box Librem 14, but I cannot promise anything,
  4. ANKER PowerCore+ 26800mAh PD 45W −− probably the one that you want to get (yet I cannot promise anything).

For example, I’ve just tested Belkin BPB002 power bank (that is not used to charge laptops anyway) and confirming that is not able to continue to charge one of my laptops while its USB-C output provides only 30W under 20V (although initially negotiated USB-PD protocol, yet charging disconnected right away, protecting Belkin BPB002 from overload, I guess).

Yes, I do hope so. But and as first step I would order only 20V PDC003 cable with E-marker plus adapter to 4.0×1.7mm. This should solve (80% chance) all of your expectations from using Anker 737 (if not insisting to use directly USB-C port for charging Librem 14), especially by rethinking about on how @carlosgonz charges his Librem laptop:

Therefore (although somewhat late reaction of mine):

Quite same item is here as well, but/or buying 1.2m 20V PDC003 cable with E-marker + physical adapter to 4.0×1.7mm would be up to your final choice. In short, there is definitively no need for another power bank, I’m quite sure. Links provided here are just as idea-wise provided.

Your feedback I’d appreciate when time comes and please keep using DC barrel there even with your powerful power bank.

EDIT: @mariapost, please make sure that any cable from certain power supply (USB-C male to USB-C male, etc.) is certified to transmit 20V/5A. I even made thread about USB4® certified cables, yet standard USB2.0 Type C cable that supports transfer of 5A current would be equally very reliable one (avoid using with the Librem 14 those USB Type C cables of up to 20V/3A). Nowadays having E-Mark chip is fine feature as well, especially if only few USB Type C cables needed (and please avoid buying USB3.1/USB3.2 cables if not really familiar with their quality background).

Here recommended approach confirmed today (only DC output voltage differs, you’ll be using adapter or cable requesting 20V PD input) as well:

@mariapost, I do not live in Poland but if you do please go ahead and buy yourself iWALK Furious 100W (26800mAh, with built-in UPD300 RISC-V chip).

Besides, my only reason (another end-user regulation related) that I cannot buy iWALK 100W PD power bank directly is following:

Is there any Anker model working out of the box?