Sony S60528 Cordless Phone Replacement Battery 3.6V 1200mAh

Sony S60528 — 3.6V Ni-MH Replacement Battery

This is a 3.6V, 1200mAh Ni-MH replacement battery for the Sony S60528 cordless phone handset. It slots into the handset battery compartment and powers the phone between charges. Voltage and capacity match the original Sony pack exactly.

• S60528 handset fit: The S60528 uses a compact single-cell NiMH pack at 3.6V nominal. This battery matches that voltage rail and physical footprint — 54.46 x 32.07 x 11.22mm — so the compartment cover closes flush and the charging contacts align with the base station cradle.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on a NiMH-compatible analyser. The BMS accepted charge current without fault, and capacity came up to rated output by the third full cycle — normal behaviour for a new NiMH cell.
• First charge on a NiMH cordless handset: Place the handset in the base for a full 16-hour slow charge before first use. NiMH cells shipped in storage state need that first long charge to reach rated capacity — a quick top-up will leave you short on talk time from day one.

Base station showing no charge light after fitting new NiMH pack

A NiMH battery sitting in storage drops well below the base station's charge-acceptance threshold — sometimes under 3.0V on a 3.6V nominal cell. Some Sony base stations interpret this low resting voltage as a missing or faulty battery and withhold charge current entirely. The fix is to leave the handset seated in the base undisturbed for at least 30 minutes. Most Sony charger circuits will detect the cell and begin a trickle charge once voltage climbs above roughly 3.2V, then switch to full charge mode.

Talk time shorter than the original battery after replacement

New NiMH cells do not deliver full rated capacity straight out of the box. The crystalline structure inside the cell needs three to five full charge-discharge cycles to reach 1200mAh. If talk time feels short in the first week, run the handset down until it prompts a low-battery warning, then return it to the base for a full 16-hour charge — repeat this three times. After conditioning, capacity stabilises at the rated figure.