Conversions
Battery Replacement Cost Calculator (Total Cost of Ownership)
Compare two battery options over the same period: purchases needed, total cost, cost per year and, optionally, cost per kWh delivered over their cycle life.
Results are mathematical estimates from the values you enter — not measurements and not data about a specific product or vehicle.
How does the Battery Replacement Cost Calculator (Total Cost of Ownership) work?
Total cost over a period = number of purchases × (price + installation), where purchases = ⌈period ÷ service life⌉. Cost per kWh delivered = (price + installation) ÷ (cycle life × capacity × depth of discharge). Enter your own quotes and the datasheet cycle life at your DoD — the defaults are only examples.
Formula
n = ⌈period ÷ life⌉
total = n × (price + installation)
per year = total ÷ period
cost/kWh = (price + installation) ÷ (cycles × Wh × DoD ÷ 1000)Worked example
10 years: A $200 lasting 4 years → 3 purchases = $600 ($60/yr); B $600 lasting 10 years → 1 purchase = $600 ($60/yr). Same total — the cycle-life inputs decide the cost per kWh.
Limitations and warnings
- Prices are yours: the calculator contains no market prices. Results are not financial advice.
- Service life depends on temperature, depth of discharge and charging; inflation and discounting are not modelled.
Four values that are often confused
- Nominal capacity (Ah)
- Charge a battery delivers under rated conditions, usually over 20 hours (C20) at 25 °C.
- Usable capacity
- The part of the nominal capacity you can use without damaging the battery — about 50% for lead-acid, 80–90% for LiFePO4.
- Cranking current (CCA)
- Current deliverable for a short time in the cold to start an engine. It measures power, not stored charge, and cannot be converted to Ah.
- Stored energy (Wh)
- Ah × voltage. The right unit to compare batteries of different voltages.