The Halo V2 series comes in three flavours: the compact Halo65 V2, a slightly larger Halo75 V2, and the num pad-touting Halo96 V2, and all of them claim significantly longer battery life thanks to the new NuPhyIO firmware. All of the keyboards feature the same 4,000 mAh battery capacity as their QMK/VIA-compatible counterparts, but QMK firmware has a reputation for not being particularly efficient, and the PCB on the NuPhyIO versions can allegedly be simpler and more integrated than the QMK PCB. 

The change to the PCB and firmware have supposedly resulted in the best-case wireless battery life (measured with no LEDs enabled) being extended from around 307 hours on the Halo96 V2 QMK/VIA to 1200 hours on the Halo96 V2 NuPhyIO version — a marked nearly 300% increase in battery life. Of course, things aren’t quite as optimistic when the backlighting comes on, with the new firmware seemingly only extending battery life by around 10%. 

In our review testing of wireless keyboards like the Keychron K4 HE, we’ve observed similar high power draw requirements from simply dialling up the RGB backlighting, although NuPhy’s testing methodology is unclear. Options like backlighting brightness and connectivity mode will make a difference to power consumption — although 2.4 GHz isn’t as much more power-hungry than you might think, given the jump from 125 Hz polling on Bluetooth to 1,000 Hz on 2.4 GHz.