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ilikepaper · 01-11-2026, 12:33 PM

In the end I just added a diode in series with the USB power pin, feeding it directly to the battery connector + terminal. And a 220uF cap after the diode, basically instead of the battery.
I had to use at least 5V/2A for USB wallwart, and a decent cable. Seems to work just fine without a battery. Added _SKIP_CHECK=1 in /etc/init.d/battcheck and dropped nobattcheck empty file in /mnt/us/system/ for good measure.

Raspberry Pi 2 cannot deliver the required current via USB, even with max_usb_current=1 using a 5V/3A power supply. So instead I used a powered USB hub, which I power with that 5V/2A wallwart, hub powers the Kindle, and it's connected to Raspberry Pi 2 via USB, seems to work great this way. Pi talks to Kindle via USB networking.

01-11-2026, 12:33 PM	#2
ilikepaper Junior Member Posts: 5 Karma: 1000 Join Date: Jan 2026 Device: k3w	In the end I just added a diode in series with the USB power pin, feeding it directly to the battery connector + terminal. And a 220uF cap after the diode, basically instead of the battery. I had to use at least 5V/2A for USB wallwart, and a decent cable. Seems to work just fine without a battery. Added _SKIP_CHECK=1 in /etc/init.d/battcheck and dropped nobattcheck empty file in /mnt/us/system/ for good measure. Raspberry Pi 2 cannot deliver the required current via USB, even with max_usb_current=1 using a 5V/3A power supply. So instead I used a powered USB hub, which I power with that 5V/2A wallwart, hub powers the Kindle, and it's connected to Raspberry Pi 2 via USB, seems to work great this way. Pi talks to Kindle via USB networking. Last edited by ilikepaper; 01-11-2026 at 12:35 PM.