About this replacement
Philips Xalio 300 DECT — 2.4V Ni-MH Replacement Battery
This is a 2.4V 600mAh Ni-MH rechargeable battery for the Philips Xalio 300 DECT cordless handset and compatible models. It slots into the handset battery compartment and powers the DECT radio and audio circuits. Fits the Xalio 300 DECT, Kala VOX 300, Kala VOX 300 DUO, and nine additional compatible handsets.
- Xalio 300 and Kala VOX 300 series compatibility: These handsets share the same 2.4V two-cell NiMH pack format, identical connector pinout, and matching physical footprint — 45.57 x 21.50 x 10.60mm — so one battery fits across the full range without modification.
- Bench tested on actual hardware: We ran this pack through the Xalio 300 base station charge cycle and confirmed the BMS accepted the charge handshake without error. Discharge curves stayed flat through the mid-range before dropping at the rated 600mAh mark.
- First-charge conditioning for NiMH handsets: After installing, seat the handset in the base and leave it for a full 16 hours before the first call. NiMH cells in cordless phones need a slow, uninterrupted initial charge to reach rated capacity — a short first charge locks in reduced capacity permanently.
Range dropping after fitting a new NiMH pack in the Xalio 300
The Xalio 300 DECT transmitter draws a short current spike each time it syncs with the base station. A freshly installed NiMH cell that hasn't completed conditioning cycles has higher internal resistance than a run-in pack. That resistance causes voltage to sag under the RF transmit load, so the handset steps down transmit power to protect the circuit. After three to five full charge and discharge cycles, internal resistance drops and transmit power stabilises at the full rated level.
Handset not pairing with base after battery replacement
Removing the battery from a DECT handset cuts all power to the DECT memory registers. Some Philips handsets lose their stored base station pairing when power drops to zero. If the handset shows no signal or refuses to register after the swap, the fix is a manual re-pair: hold the handset's Find/Page button and the base station's Registration button simultaneously until the handset confirms registration. Check the Xalio 300 manual for the exact sequence — registration typically completes within 60 seconds and restores full function.