Feetong D8628 Replacement Battery 3.7V 1500mAh

Feetong D8628 / ZW-100 — 3.7V Li-ion Replacement Battery (LiLTG-02M0D484261)

This is a 3.7V 1500mAh Li-ion replacement battery for the Feetong D8628 and ZW-100 portable mobile hotspot devices. It uses OEM part number LiLTG-02M0D484261 and matches the original cell's dimensions at 64.98 × 41.90 × 4.90mm. Swap it in when the original battery no longer holds charge or the hotspot shuts down under load.

• D8628 and ZW-100 compatibility: Both models run the same 3.7V power rail, share the same physical form factor, and use identical BMS handshake logic — one battery covers either device without modification.
• Bench tested on actual hardware: We ran this cell under combined modem and Wi-Fi load at maximum connected clients. The BMS held voltage steady through the draw spike and did not trip a false low-voltage cutoff during startup.
• Cellular signal and battery load: Keep the hotspot close to a window or near a strong signal source during long sessions. Weak cellular signal forces the modem to transmit at maximum output power continuously, which pushes significantly more current draw through the battery than normal operation.

Why the D8628 drops Wi-Fi clients mid-session under a fresh battery

The D8628 runs two simultaneous radio loads — the cellular modem and the Wi-Fi access point. At maximum client connections, the combined current draw can cause a brief voltage sag that the BMS reads as a low-cell event, triggering a temporary shutdown of the Wi-Fi radio. This is not a battery fault — it is a BMS protection response to transient current spikes. Keeping total connected clients below the device maximum and ensuring good cellular signal reduces the frequency of these sag events.

Hotspot shows charged but won't complete boot after sitting unused

If the D8628 sat in storage for several weeks or months, the cell may have self-discharged below the minimum boot voltage — typically under 3.0V for this cell chemistry. The device shows a charge indicator because the BMS accepts current, but the system voltage is still too low to complete the boot sequence. Connect the hotspot to a charger and leave it for 20–30 minutes before attempting to power on again. If the cell recovers, it will reach approximately 3.2–3.4V and the boot sequence will complete normally.