Medion MD81877 Cordless Phone Replacement Battery 2.4V 600mAh

Medion MD81877 / Slim DECT 500 Series — 2.4V Ni-MH Replacement Battery (5M702BMX)

This 2.4V, 600mAh Ni-MH battery replaces the original pack in Medion cordless DECT handsets including the MD81877, MD82877, Life S63006, and Slim DECT 500 series. It matches the OEM voltage and cell format so the handset seats correctly in the base station charging cradle. Capacity is 600mAh — use the product data figure, not the cell markings on older OEM packs.

• MD81877 / MD82877 / Slim DECT 500 fit: These handsets share the same 2.4V two-cell NiMH architecture, connector pinout, and cradle contact spacing. One battery format covers all of them — voltage rail and physical dimensions are identical across the range.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on a DECT handset cradle and confirmed the BMS accepted charge without triggering a fault light. Voltage at full charge measured within the base station's acceptance window.
• First charge on DECT NiMH packs: Place the handset in the base immediately after installing the new battery. Leave it on charge for a full 16 hours before first use. NiMH cells in cordless phones need this slow initial charge to reach rated capacity — a short charge first time results in reduced talk time across every subsequent cycle.

Base station charge light not activating on a new NiMH pack

NiMH batteries lose voltage during storage. If a new pack arrives with cell voltage below roughly 2.0V, some Medion base stations will not initiate a charge cycle — the charging circuit expects a minimum voltage before it engages. Remove the handset, wait 30 seconds, then reseat it firmly so both cradle contacts are fully engaged. If the charge light still does not activate, connect the base station to a different mains socket to rule out a low-voltage supply issue, then reseat again.

Talk time noticeably shorter than the original battery for the first few uses

This is normal behaviour for NiMH cells and not a fault. Fresh NiMH batteries do not reach rated capacity on the first charge cycle — it typically takes three to five full charge-and-discharge cycles before the cells stabilise at 600mAh. Each cycle slightly increases delivered capacity until the pack settles. Run the handset until it signals low battery, return it to the base for a full charge, and repeat — by cycle four or five, talk time will reflect the rated figure.