Battery observed-range linear fade fit calculator

Calculate fitted capacity slope and fitted capacity at query with your own figures.

Your numbers

Use the units shown. Results update as you change valid inputs.

Use fitted capacity slope and fitted capacity at query to compare changes to your inputs. The method and limits below explain the scope.

Examples

Examples

Try the starting example

Equivalent-cycle ages (cycles)
0,100,200,300
Measured capacities (Ah)
100,98,95,92
Query cycle age within observed range
150
Fitted capacity slope (Ah/cycle)
-0.027
Fitted capacity at query (Ah)
96.25
Residual capacities (JSON)
[-0.3,0.4,0.1,-0.2]

Try another scenario

Equivalent-cycle ages (cycles)
[1, 100, 200, 300]
Measured capacities (Ah)
[100, 98, 95, 92]
Query cycle age within observed range
150
Fitted capacity slope (Ah/cycle)
-0.027087
Fitted capacity at query (Ah)
96.256772
Residual capacities (JSON)
[-0.292752121447,0.388872401322,0.0975840404823,-0.193704320357]
Calculation method

Calculation method

Fitted capacity slope (Ah/cycle)

Least-squares linear measured-capacity trend; query limited to observed cycle range, no life extrapolation.

Fitted capacity at query (Ah)

Least-squares linear measured-capacity trend; query limited to observed cycle range, no life extrapolation.

Residual capacities (JSON)

Least-squares linear measured-capacity trend; query limited to observed cycle range, no life extrapolation.

Symbols and units
a
Equivalent-cycle ages (cycles)
b
Measured capacities (Ah)
c
Query cycle age within observed range

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions & limits

Assumptions & limits

  • User-supplied measurements and assumptions; Least-squares linear measured-capacity trend; query limited to observed cycle range, no life extrapolation. Supported limits: Finite numeric values bounded to 1e9 magnitude; lists and tables contain 1–100 records unless a stricter bound is stated. Inputs use the units shown. Lists explicitly paired by a method must have matching lengths; independent polynomial coefficient vectors may differ. Respect stated physical, interpolation, policy and computational domain limits.
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Further reading

Method reference ↗

Background reading; this does not imply endorsement or independent review of SumFizz.

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