AT&T E1937B Cordless Phone Compatible Battery 3.6V 700mAh

AT&T E1937B / E5912 Series — 3.6V Ni-MH Replacement Battery (89-0099-00-00)

This is a 3.6V, 700mAh Ni-MH battery for AT&T cordless phone handsets including the E1937B, E560-2, E560-5, and E5912, plus sixteen additional models in the same family. It replaces OEM part numbers 5-2459, 5-2523, 89-0099-00-00, and B27910. Install it when the original pack no longer holds a charge or the handset dies mid-call.

• E560 and E5912 family fit: These models share the same 3.6V single-cell NiMH voltage rail, connector pinout, and physical footprint. The base station charging circuit reads the same contact arrangement across the range, so one pack covers the full lineup without modification.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on AT&T handset hardware. The BMS accepted charge from the base station on the first dock without a conditioning step, and voltage held steady under the handset's RF transmit load.
• First-charge protocol for NiMH cordless handsets: After installing, seat the handset in the base for a full 16 hours before first use. NiMH cells in cordless phones need a slow initial charge to reach rated capacity — skipping this step is the most common reason a new pack underperforms.

Talk time shorter than original battery after replacement

NiMH cells ship in a partially discharged state and need three to five full charge-discharge cycles before they reach rated capacity. On cycle one, talk time may feel noticeably shorter than the original pack. Each full cycle brings voltage recovery closer to the 700mAh rating. By cycle five, performance should match or exceed the worn pack you replaced.

Base station showing no charge or error light after swap

A NiMH pack that has sat in storage can drop below the voltage threshold the base station uses to confirm a valid battery is present. When voltage reads too low, the base interprets it as an absent or faulty cell and stops the charge cycle. Place the handset in the base for at least 30 minutes without removing it — most AT&T base circuits will retry the charge initiation once the pack reaches approximately 3.0V. If the error light persists past that point, check that the handset contacts are clean and fully seated.