JDSU A6188-67004 Compatible Battery 11.1V 7800mAh Li-ion

JDSU A6188-67004 — 11.1V Li-ion Replacement Battery

This is an 11.1V lithium-ion battery rated at 7800mAh (86.58Wh), cross-referenced to OEM part numbers including A6188-67004, 1420-0868, LI204SX, NI2040, and related variants. It fits JDSU Acterna handheld test equipment used in fiber optic and telecommunications field diagnostics. If your unit currently accepts any of the listed OEM part numbers, this battery fits the same bay and connector.

• Cross-reference coverage across LI204SX and NI2040 variants: JDSU used multiple part numbers across production runs of the same physical battery — LI204SX-60, LI204SX-66A, NI2040A22, NI2040HD24, and others share the same 11.1V three-cell Li-ion configuration, connector pinout, and BMS handshake protocol. One replacement covers the full variant family.
• Bench tested on actual hardware: We ran this cell through charge and load cycles on test equipment to confirm BMS communication, charge acceptance, and cutoff thresholds. The protection circuit behaved as expected at both low-voltage cutoff and thermal limits.
• Power-on self-test cycle: After installing this battery, let the device complete its full startup self-test without interruption. JDSU test equipment runs a BMS verification sequence at boot — cutting power during this window logs a false battery fault that persists until the next clean reboot cycle.

Why JDSU test equipment rejects a new battery on first boot

JDSU Acterna units store a battery state profile in firmware. When a new cell goes in, the BMS compares internal resistance and resting voltage against the stored OEM profile. A new cell that hasn't completed an initial charge-discharge cycle often reads slightly outside that profile's accepted window, triggering a rejection flag. This is not a defective battery — it's the learn cycle not yet complete. Run one full charge from flat to 100%, then discharge the unit normally through a full test session. After that cycle, the BMS recalibrates to the new cell's actual characteristics and the warning clears.

Charge indicator stalls below 100% on first charge

On the first charge, the device's charge IC applies a conservative current limit to an unrecognised cell, which causes the charge indicator to plateau around 85–95% and stop climbing. This is a deliberate firmware behaviour, not a fault with the battery or charger. Leave the unit on charge without interruption — the IC will eventually push through the plateau once internal resistance drops as the cell warms up through the charge cycle. After the first full cycle completes, subsequent charges will reach 100% normally and the indicator will behave as expected.