GP 2.4V Cordless Phone Replacement Battery GP0735 600mAh Ni-MH

GP GP0735 / GP0747 / GP0748 — 2.4V Ni-MH 600mAh Replacement Battery

This is a 2.4V, 600mAh Ni-MH replacement battery for GP cordless phone handsets. It cross-references OEM part numbers GP0735, GP0747, GP0748, 5M702BMX, GP0827, GP0845, GPH170-R05, GP1050, and GPHP70-R05. If your handset won't hold a charge through a normal day of calls, this pack replaces the original cell directly.

• Multi-OEM cross-reference: These part numbers cover GP handsets that share the same 2.4V two-cell NiMH architecture, connector pinout, and BMS charge acceptance profile — which is why one pack covers all of them.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on a cordless phone base station. The BMS accepted charge normally from cycle one, and voltage held steady at 2.4V under simulated RF transmit load without sagging below the handset's low-battery cutoff threshold.
• First-charge conditioning for NiMH cordless packs: After installing, seat the handset in the base and leave it for a full 16 hours before first use. NiMH cells in cordless phones need a slow initial charge to reach rated 600mAh capacity — short first charges leave the cells partially formed and talk time suffers for weeks.

Why range drops after a NiMH battery swap in a cordless handset

DECT handsets pull a burst of current every time the RF module transmits. A fresh NiMH pack that hasn't completed its first full conditioning cycle has higher internal resistance than a fully formed cell. That resistance causes voltage to sag during each transmit burst, which the handset interprets as low battery and reduces transmit power — cutting range. Running three to five full charge and discharge cycles brings internal resistance down to spec and restores normal transmit power levels.

Base station not registering a charge on a new NiMH pack

NiMH batteries stored in a warehouse self-discharge over time and can arrive below the voltage threshold the base station uses to confirm a valid pack is seated. If the charge indicator doesn't light or shows an error, the base may be rejecting the pack as too flat to charge safely. Place the handset firmly in the cradle and wait up to 30 minutes — some bases trickle at a very low rate to bring a deeply discharged NiMH cell back above the acceptance threshold before switching to normal charge current. If the light still doesn't activate after 30 minutes, reseat the handset and confirm the battery contacts are clean and making full contact.