Swissvoice DP500 Replacement Battery 2.4V 500mAh Ni-MH

Swissvoice DP500 / DP550 Series — 2.4V Ni-MH Replacement Battery (GP1010)

This is a 2.4V, 500mAh Ni-MH battery for the Swissvoice DP500, DP500 Eco Plus, DP550, and DP550 Eco Plus cordless handsets. It replaces OEM part numbers GP1010 and VT50AAAALH2BMJZ. When the original pack stops holding a charge, this swap restores the handset to normal operation without buying a new phone.

• DP500 and DP550 compatibility: Both the standard and Eco Plus variants share the same handset chassis, connector pinout, and 2.4V NiMH cell configuration. One pack covers the full range of these models.
• Bench tested on actual hardware: We ran this pack through charge and discharge cycles on a DP500 handset. The BMS accepted charge from the base station immediately, and voltage held stable across the RF transmit load without triggering a low-battery cutoff during standby.
• First charge protocol for NiMH handsets: After fitting, seat the handset in the base and leave it there for a full 16 hours before the first call. NiMH cells from storage have reduced initial capacity — a slow first charge lets them reach rated 500mAh. Skip this and the first few talk sessions will feel short.

Talk time shorter than expected after battery swap

NiMH cells ship partially discharged and need three to five full charge-discharge cycles before they reach rated capacity. If the first few uses feel short, that is not a fault — the cells are conditioning. Each full cycle gradually increases the usable capacity. By cycle four or five, talk time should match the original pack's rated performance.

Base station not charging the new pack — error light stays on

NiMH packs that have sat in storage drop to very low resting voltages — sometimes below the threshold the base station's charge controller will accept. The base reads the low voltage as a fault rather than an empty cell. Remove the handset, leave it out of the base for 30 seconds, then re-seat it firmly. If the error persists, a trickle charge using a compatible external NiMH charger for 15 minutes will raise the cell voltage to approximately 1.0V per cell, which is enough for the base to recognise and resume charging.