About this replacement
Sony CCD-TRV108 / CCD-TRV138 Series — 7.4V Li-ion Replacement Battery (NP-QM71)
This 7.4V 2800mAh Li-ion cell replaces the NP-QM71, NP-QM70, NP-FM70, and NP-FM71 in Sony MiniDV Handycam camcorders. It fits the CCD-TRV108, CCD-TRV118, CCD-TRV128, CCD-TRV138, and over 60 additional Sony camcorder models sharing the same InfoLITHIUM battery bay. Capacity is 2800mAh (20.72Wh) — matched directly to the product specification, not extrapolated.
- CCD-TRV series cross-compatibility: The TRV108 through TRV138 share a common 7.4V InfoLITHIUM battery bay and the same BMS handshake protocol. All four models read the same battery identification signal, so one cell covers the full range without connector or voltage mismatches.
- Bench tested on actual hardware: We ran this cell through the CCD-TRV108's charging circuit and monitored BMS communication during charge and discharge. The InfoLITHIUM charge management protocol accepted the cell on first insertion and the remaining-charge indicator tracked consistently through the full discharge curve.
- First charge via camera body: On first use, charge this cell inside the camcorder body — not an aftermarket external charger — before recording. The Sony InfoLITHIUM BMS maps the cell's discharge curve during this initial in-body charge cycle, which is what drives the on-screen remaining time display. Skipping this step produces an inaccurate readout.
Why the CCD-TRV108 rejects a new battery on first install
Sony's InfoLITHIUM system authenticates a new cell through a short handshake when power is first applied. If the camera has been in storage or the contacts are oxidised, it may display a battery error or simply not power on. The fix is straightforward: seat the battery firmly, connect the AC adapter, and allow the camera to begin a supervised charge. This prompts the BMS to complete authentication rather than relying on a cold power-on check alone.
Battery percentage jumping erratically on the CCD-TRV108 display
The InfoLITHIUM percentage readout maps voltage thresholds to a remaining-time estimate calibrated to the original cell's discharge profile. A new cell — or one with a slightly different internal resistance — will initially hit those thresholds at unexpected points, causing the counter to jump. This is not a fault with the cell; it is the BMS recalibrating its estimate. Run the battery down to the camera's auto-shutoff point and then charge it fully in-body once. After that conditioning cycle the readout stabilises to within a few percentage points of actual state of charge.