Motorola MD7151 Replacement Battery 3.6V 700mAh 525734-001

Motorola MD7151 / MD7161 Series — 3.6V Ni-MH Replacement Battery (525734-001)

This is a 3.6V, 700mAh Ni-MH battery pack for the Motorola MD7151 and MD7161 series cordless handsets. It replaces OEM part numbers 525734-001 and TL26158. Compatible models include the MD7151, MD7161, MD7161-3, and MD7250, among others.

• MD7151 / MD7161 series fit: These models share the same 3.6V three-cell Ni-MH pack format, connector pinout, and physical footprint. The base station's charge circuit expects this voltage range, so swapping between models in this family works without modification.
• Bench tested on actual hardware: We ran charge and discharge cycles on the MD7161 platform. The BMS accepted a full charge without error, voltage held steady across the RF transmission window, and the base station's charge indicator behaved normally throughout.
• First charge on Ni-MH cordless packs: After installing this battery, place the handset in the base for a full 16-hour charge before first use. Ni-MH cells in cordless phone packs ship partially discharged. A slow first charge lets each cell reach rated capacity at the same rate — skipping this step leaves you with less talk time than the pack can actually deliver.

Talk time shorter than the original battery after replacement

New Ni-MH cells don't reach rated capacity on the first cycle. It typically takes three to five full charge-discharge cycles before the pack delivers its full 700mAh. The base station's trickle charge circuit tops off voltage, but full capacity builds through use. Run the handset until the low-battery tone sounds, then return it to the base — repeat this a few times and talk time will improve with each cycle.

Base station showing no charge or error light after installing the new pack

Ni-MH packs lose voltage during storage. If the pack voltage drops below roughly 3.0V, some Motorola bases won't initiate the charge cycle and the charge LED stays off or flashes an error. Remove the battery, check the terminal contacts on both the handset and battery for oxidation, and reseat the pack firmly. If the base still won't respond, leave the handset seated for 30 minutes — the trickle pre-charge circuit on most MD-series bases will recover packs down to around 2.7V before switching to full charge mode.