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Battery

The Web3 Pi UPS uses Sony NP-F series batteries — 7.2 V Li-Ion camera packs that are cheap, widely available, and user-replaceable. The pack slides onto a standard NP-F rail on top of the unit.

Sony NP-F970, NP-F770 and NP-F570 batteries

Supported Models

Model Capacity Runtime
NP-F570 2600 mAh (18.7 Wh) Shortest — most compact
NP-F770 5200 mAh (38.5 Wh) Mid-range
NP-F970 9600 mAh (71 Wh) Longest

Runtime depends on your Raspberry Pi's workload; other NP-F-compatible packs also fit. Capacities above are for the recommended Newell packs — see Specifications for links.

Use packs with internal protection

The UPS relies on the battery's own built-in protection circuit (BMS) for cell-level and deep-discharge protection. Use quality NP-F packs that include one — virtually all genuine and reputable third-party packs do.

Inserting and Removing

  • Insert: set the battery on the top rail offset by about half its length — NP-F packs engage the rail from roughly their midpoint — then slide it on until the red PUSH latch clicks.
  • Remove: press the red PUSH latch on the side edge and slide the battery off the rail.

Hot-Swap

The battery can be swapped while external power is present (USB-C IN or the barrel jack) — the output to the Pi stays up the whole time.

Check before you pull

Before swapping, confirm the unit is not running on battery: the Home screen mode should read anything other than DSC (discharging). Removing the battery while it is the only power source cuts power to the Pi.

Charging

Charging is fully automatic — there is nothing to configure:

  • Whenever external power is present and the pack is below full, the UPS charges it.
  • Charging is deliberately gentle: a modest charge current and a ~8.1 V "gentle full" target (below the pack's maximum) extend battery lifespan.
  • When the pack is full, charging stops: the mode label shows FUL, then IDL. On external power the Pi is always fed from the input, so a full pack simply rests — and takes over seamlessly if the input fails.
  • When power returns after an outage, charging resumes on its own.

Reading Charge State on the OLED

The Home screen shows a battery icon (fill level = charge, scrolling bars while charging, blinking below 10 % on battery), the charge percentage, and a mode label. The BATTERY debug screen (current firmware only) adds battery voltage and charge current.

Label Meaning
DSC Discharging — running on battery
PRE Pre-charge (deeply discharged pack)
CHG Charging
FUL Full
IDL On external power, not charging

On battery, the buzzer beeps once every 30 s below 20 % charge and twice every 5 s below 10 %; the companion service can shut the Pi down safely before the battery runs out — see Host Integration.

Note

The charge percentage is estimated from battery voltage and can read optimistically while charging.

See Display & Menu for the full screen reference and Power for failover and charging behavior in detail.