About this replacement
Beaba Babyphone Audio Simply Zen — 3.7V Li-Polymer Replacement Battery (800974)
This is a 3.7V, 700mAh Li-Polymer replacement battery for the Beaba Babyphone Audio Simply Zen and Simply Zen 2.0 parent units. Part number 800974. It powers the handheld receiver that keeps you connected to the nursery transmitter over the audio link.
- Simply Zen and Simply Zen 2.0 compatibility: Both monitor generations use the same 3.7V single-cell Li-Polymer pack with identical connector pinout and BMS handshake. One battery covers both versions without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the parent unit's charging circuit. The BMS accepted the charge profile without fault flags and held stable voltage across the audio receive circuitry.
- Re-pairing after battery swap: When the parent unit loses power completely — which happens during a battery replacement — it drops its stored wireless link to the nursery unit. After fitting the new battery, hold the pairing button on both units until the connection indicator confirms a fresh link. Skipping this step leaves the receiver silent even with a fully charged battery.
Parent unit battery draining faster overnight than during the day
Night-time monitoring is a sustained high-draw condition. The parent unit keeps its screen active, maintains the radio link, and in many operating modes runs audio squelch continuously. A 700mAh cell at 3.7V carries 2.59Wh — that budget gets consumed faster when the screen stays on for hours without interaction. Enable the screen timeout or VOX mode so the unit only activates on sound. Those two settings significantly reduce overnight draw from this small cell.
Reduced wireless range from the parent unit after fitting a new battery
Radio transmission power in the parent unit is voltage-sensitive. If you install the battery and immediately walk to another room, the cell may not yet be at full charge voltage — typically 4.2V for a Li-Polymer cell of this type. A partially charged cell causes the radio section to operate below its rated power level, which cuts usable range. Charge the parent unit fully before testing range. At 4.2V output, the transmitter runs at its rated power and range returns to specification.