Htc One not booting into custom recovery

Hey guys!
I wanted to root my HTC One M8 and ran into a little problem doing so.
This is what I have done:

• Unlock bootloader through HTC Dev


• Flashing the unlock.bin


• Bootloader is now unlocked


• Flash TWRP


• Erase cache


• Boot into Recovery

However, instead of seeing the familiar TWRP screen like on my previous phones, the phone shuts down completely after shortly showing the HTC logo. This is my getvar output:

Quote:

version: 0.5 version-bootloader: 3.19.0.0000 version-baseband: 1.0.U20410.1@50408 version-cpld: None version-microp: None version-main: 1.11.401.2 version-misc: PVT SHIP S-ON serialno: HT547YS00641 imei: //obscured imei2: Not Support meid: 00000000000000 product: m8ql_ul platform: hTCBmsm8939 modelid: 0PKV10000 cidnum: HTC__031 battery-status: good battery-voltage: 0mV partition-layout: Generic security: on build-mode: SHIP boot-mode: FASTBOOT commitno-bootloader: d5ccbaf7 hbootpreupdate: 11 gencheckpt: 0 mfg-name: 0001

I have tried multiple versions of both TWRP and CWM, but neither do anything. It should also be noted, that when the cable is still plugged in, the orange low-battery indicator LED starts blinking, together with my screen flickering on and off (intervals of 5 seconds) with big battery charging sign on it. Could this be a battery problem? The phone boots normally into the Stock ROM.