| Parameter Item | Specification |
|---|---|
| Model Number | WJ‑4/5AAA400 |
| Nominal Voltage | 1.2V per cell |
| Rated Capacity | 400mAh (Minimum 360mAh) |
| Cell Size | 4/5AAA Cylindrical Ni‑MH |
| Dimension (D×H) | Φ10.5mm × 42.0mm |
| Weight | Approx 8.5g |
| Internal Resistance (1kHz, fully charged) | ≤ 75 mΩ |
| IEC Cycle Life | ≥450 cycles (IEC61951‑2:2017) |
| Max Continuous Discharge Current | 400mA (1C) |
| Standard Charge | 40mA (0.1C), 16 hours |
| Fast Charge | 200mA‑400mA with delta‑V charge‑termination control |
| Discharge Temperature Range | -10℃ ~ +55℃ |
| Short‑term Storage Temperature (<30 days) | -20℃ ~ +55℃ |
| Cut‑off Discharge Voltage | 1.0V/cell |
| 28‑day Self‑discharge Retention | ≥60% capacity @20℃ |
| Certifications | PPWR,CE, RoHS, REACH, MSDS documents available |
We provide OEM & ODM custom assembly service based on WJ‑4/5AAA400 miniature Ni‑MH cells. We support series‑parallel combination, spot‑weld tiny metal tabs, thin flying leads, micro‑connectors and mini plastic housings for ultra‑compact device layout.

4/5AAA 400mAh miniature nickel‑metal hydride cell is designed for compact low‑power sensors, small household safety and mini portable electronic hardware.
Weijiang Power is a professional Ni‑MH rechargeable battery manufacturer with 16‑year production experience. In‑house reliability laboratory and automated production lines support mass‑volume orders and small‑batch miniature OEM customization. Full export‑ready certification documents for worldwide customers.
Contact us for bulk price, spot‑welded cell options, miniature OEM pack solution and download official technical datasheet.



