JVC BN-V812 Replacement Battery 7.4V 2900mAh Li-ion

JVC GR-DLS1U / GR-DV9000 Series — 7.4V Li-ion Replacement Battery (BN-V812)

This 7.4V, 2900mAh Li-ion battery replaces the BN-V812, BN-V812U, BN-V814, and BN-V814U cells used in JVC MiniDV camcorders including the GR-DLS1U, GR-DV9000, GR-DVL, and GR-DVL9000. It slots into the original battery bay and connects to the camcorder's onboard BMS through the same multi-pin contact layout as the factory cell. Capacity is rated at 2900mAh / 21.46Wh.

• GR-DLS1U and GR-DV9000 series compatibility: These models share a common 7.4V two-cell Li-ion architecture and the same BN-V81x connector footprint. The BMS on each body uses the same voltage-threshold handshake, so one cell supports the full listed range without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a GR-series body. The BMS accepted the cell on first connection, engaged charge termination at the correct cutoff voltage, and reported charge status through the camcorder's indicator without error.
• First-use charge protocol for GR-series bodies: Charge the new cell inside the camcorder body or OEM charger before recording. The GR-series BMS maps its remaining-charge display against a discharge curve it calibrates on the first full cycle — skipping this step causes the indicator to read inaccurately from the start.

Why the GR-DLS1U shows a low-battery warning on a freshly charged replacement cell

The GR-DLS1U uses a voltage-threshold model to estimate charge level rather than a fuel gauge IC. A new cell has a slightly different internal resistance profile than an aged OEM cell, which shifts the voltage readings the BMS uses as reference points. Until the cell completes at least one full charge-discharge cycle inside the body, the BMS can misread a 90% charge as 40–50%. One complete cycle resets the threshold mapping and brings the indicator in line with actual capacity.

Camcorder cuts to standby mid-recording even though the battery indicator shows charge remaining

This happens when the cell voltage sags below the BMS cutoff threshold under the combined load of the CCD sensor, LCD panel, and tape transport motor — even if the resting voltage looks acceptable. It is common with cells that have been stored discharged for extended periods before first use, as the cell's internal resistance rises during storage. Reconnect the battery, power the camcorder on without recording, and allow the cell to warm to room temperature before attempting playback or record. If the problem persists, run a full charge cycle; a healthy cell should hold above 6.8V under record load.