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How long will your Pytes battery last?
Enter your system and your average consumption: the calculator gives the usable energy, the hours of autonomy and the time the batteries reach your cut-off.
A Pytes E-Box 48100R stores 4.8 kWh (48 V, 100 Ah), a V5 module 5.12 kWh. The calculator starts with one E-Box: change the number of modules and the capacity to match your stack.
Pytes Monitor does this calculation live, with your real consumption: the dashboard shows when the batteries will be full or reach your cut-off. See it in the demo →
The formula
autonomy = capacity × health × (charge − cut-off) × efficiency ÷ (consumption + inverter’s own consumption)
Example with one E-Box 48100R: 4.8 kWh, from 90 % to a 10 % cut-off, behind an inverter at 92 % that uses 40 W for itself, with the house drawing 400 W on average: 4.8 × 0.8 × 0.92 ÷ 0.44 ≈ 8 hours.
Why real runtime is often shorter
- One weak cell ends the discharge. The BMS stops the battery when its lowest cell reaches its limit, even if the others still hold energy. A growing cell spread shortens the night.
- The displayed charge drifts. The state of charge is counted, not measured: without a full charge from time to time, it can be several points off.
- Cold reduces what you can take out. Below about 10 °C a lithium battery delivers less, and many BMS limit the current.
- Peaks cost more than the average. A kettle or a pump at 2 kW for a few minutes weighs more than its share, because of losses and current limits.
Typical night consumption in a home is 100 to 250 W; in the evening, 400 to 1,000 W. Your own figure is on the dashboard of your box after a few days.
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