About this replacement
Sharp SH5010C / SH5018C / SH5020C — 3.7V Li-ion Replacement Battery (EA-BL22)
This is a 3.7V, 600mAh Li-ion replacement battery for the Sharp SH5010C, SH5018C, and SH5020C smartphones. It carries OEM part number EA-BL22 and matches the original cell's voltage rail and connector pinout. Swap it when the original cell no longer holds a usable charge or causes unexpected shutdowns.
- SH5010C / SH5018C / SH5020C fit group: These three models share the same battery bay dimensions, 3.7V nominal rail, and EA-BL22 connector. The BMS handshake protocol is identical across the group, so one cell covers all three without modification.
- Bench tested on actual hardware: We cycled this cell through charge and load on the bench. The BMS accepted the charge handshake cleanly, held voltage under screen-on and modem load, and tripped the low-voltage cutoff at the correct threshold without early dropout.
- Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one full discharge-charge cycle. The fuel gauge IC in these Sharp models was calibrated to the old cell's discharge curve. One slow cycle lets it recalibrate against the new cell before fast-charge currents are applied to an uncalibrated coulomb counter.
Sudden shutdown at 20–30% on the SH5010C after a cell swap
The SH5010C's fuel gauge IC maps reported percentage to a voltage curve learned from the original cell. A new cell with a slightly different discharge curve hits a steep voltage cliff earlier than the IC expects. When the modem or display draws peak current, cell voltage drops below the BMS cutoff threshold even though the gauge still reads 20–30%. The phone interprets this as a hard fault and shuts down. Run one full slow discharge to around 3.0V at the terminal, then a full charge — this resets the IC's learned curve to match the new cell.
Phone won't power on after the replacement battery sat in storage
Li-ion cells self-discharge during storage. If the EA-BL22 cell dropped below approximately 2.5V per cell, the BMS enters a lockout state to prevent damage and will not pass current to the phone's power rail. Plugging in the charger may show no response at all — no charging indicator, no boot. Connect the phone to a wall charger and leave it undisturbed for 15–20 minutes. The charge IC trickle-charges the cell back above the BMS re-enable threshold, typically around 2.8–3.0V, at which point the BMS releases and normal charging resumes.