Audioline DECT 7500 Replacement Battery 2.4V 400mAh SL30013

Audioline DECT 7500 Series — 2.4V Ni-MH Replacement Battery (SL30013)

This is a 2.4V, 400mAh Ni-MH rechargeable battery that fits the Audioline DECT 7500 handset. It replaces part number SL30013 and covers the DECT 7500, DECT 7500 Micro, DECT 7501, and DECT 7800 among others. When the original cell degrades and the handset stops holding charge, this pack restores the handset to working order.

• DECT 7500 series compatibility: These models share the same 2.4V two-cell NiMH pack format, connector orientation, and physical footprint. The SL30013 part number covers all of them because the handset chassis and charging circuit did not change across this range.
• Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on a DECT 7500 handset. The BMS accepted the pack without error, the base station registered a charging state immediately, and voltage held steady under RF transmit load throughout testing.
• First charge after installation: Place the handset in the base and leave it for a full 16 hours before using it. NiMH cells in cordless phone packs ship partially discharged. A slow first charge lets the cells reach rated capacity and sets the baseline the base station uses to judge charge state on every subsequent cycle.

Talk time shorter than expected after fitting the new pack

NiMH cells do not reach rated capacity on the first cycle. The electrochemical structure needs three to five full charge and discharge cycles before the cells deliver their full 400mAh. If talk time seems short in the first week, that is normal behaviour — not a fault. Run the handset until it drops out, return it to the base for a full charge, and repeat. By the fifth cycle, capacity will be at or near spec.

Base station charge light stays off or shows an error after swap

NiMH packs lose voltage during storage. If the cell voltage drops far enough, the base station's charge acceptance circuit may not recognise it as a valid battery. The fix is to seat the handset firmly in the base and leave it undisturbed for at least 30 minutes — most Audioline base units will begin a trickle charge at that point and the charge light will come on once voltage climbs above the acceptance threshold. If the light still does not appear, remove and reseat the handset, confirming the battery contacts are clean and making full contact. The pack needs to read above roughly 2.0V for the base to engage the full charge cycle.