GoPro Hero 4 Replacement Battery 3.7V 950mAh AHDBT-401

GoPro Hero 4 Series — 3.7V Li-ion Replacement Battery (AHDBT-401)

This 3.7V, 950mAh Li-ion cell is a direct replacement for the AHDBT-401 battery used in the GoPro Hero 4, Hero 4 Silver, Hero 4 Black, and Hero 4+. It fits the same compact 36.03 x 32.56 x 10.25mm footprint as the original. Capacity matches OEM spec at 3.52Wh.

• Hero 4 platform compatibility: The Hero 4, Hero 4 Silver, Hero 4 Black, and Hero 4+ all share the same battery bay geometry and the AHDBT-401 cell spec. Same voltage rail, same connector orientation, same BMS communication protocol across every variant in this generation.
• Bench tested on actual hardware: We ran this cell in a Hero 4 Black body. The BMS accepted the cell after one full charge cycle via the camera body. Voltage held stable through sustained 1080p60 recording with Wi-Fi active.
• First-cycle initialisation on Hero 4: Before shooting, run one full charge cycle from inside the camera body using the OEM USB cable. Some Hero 4 units need this step to map the new cell's discharge curve — skipping it can cause the battery indicator to read incorrectly from the first session.

Why Hero 4 battery percentage jumps erratically after fitting a new cell

The Hero 4 battery gauge maps percentage to a voltage-threshold table calibrated to the original cell's discharge curve. A new cell — even at identical spec — discharges slightly differently until the BMS logs a full cycle. This mismatch causes the indicator to jump from 80% to 40% with no warning, or to show full charge when the cell is already past its midpoint. One complete charge and discharge cycle inside the camera body resolves this. After that cycle, the gauge reads consistently.

Hero 4 displaying dead battery icon on a partially charged replacement

This happens when the cell voltage drops below the Hero 4's low-voltage detection threshold during a high-draw moment — typically when Wi-Fi transmits or video encoding spikes. The camera reads an instantaneous sag as a dead battery and shuts down, even though resting voltage is still above 3.5V. The fix is to charge the cell to 100% before the session and disable Wi-Fi if you're not actively using it. If the problem persists after a full charge, check that the battery contacts in the bay are clean and seated flat.