If you need second factor, first factor and charge time and you already have battery capacity, charging current, current state of charge (soc) and battery type, this calculator does the substitution for you. It suits a quick check, a homework answer you want to confirm, or any figure you need to sanity test.
What Is the Battery Charge Time Calculator?
The battery charge time calculator turns battery capacity, charging current, current state of charge (soc) and battery type into second factor, first factor and charge time.
It is a quick way to get from the numbers you have to the number you need, without setting up a spreadsheet or reaching for a formula.
How the Battery Charge Time Works
Each result follows from the ones before it, and the calculator shows every step, so a surprising answer can be traced back to the input that caused it.
Round your inputs to the precision you actually know, and keep more precision than that in the intermediate steps.
Getting a Result You Can Trust
Run the calculation twice with slightly different inputs. A sensible calculator moves its output in proportion; a wild change points to a unit or a decimal point problem in what you entered.
Write the inputs down next to the answer. It takes a moment and it is the difference between a number you can explain and one you cannot.
A Worked Example
Working through an example, with battery capacity set to 10, charging current set to 5, current state of charge (soc) set to 2, the calculator returns first factor of 9.8, and second factor of 4.75, and charge time of 2.063. Substitute your own figures and the same steps produce the same kind of answer.
Frequently Asked Questions
What do I need to work out second factor?
Enter battery capacity, charging current, current state of charge (soc) and battery type. The calculator then works through the relationship and reports second factor, first factor and charge time.
What does the battery charge time actually calculate?
It takes battery capacity, charging current, current state of charge (soc) and battery type and converts them into second factor, first factor and charge time using the standard relationship for this problem. Each step is applied in turn, so every output is traceable back to the numbers you typed in.
How should I enter battery capacity?
Use the value you actually have, in the unit shown next to the field. Enter every value in the same unit system. The calculator assumes the figures you supply are consistent, so it cannot correct a mistake that happens before the calculation starts.
Do I have to fill in every field?
Only the fields a particular result depends on. If you leave one blank, the results that need it simply show a note instead of a number, and everything else still works.
Can I use this for a quick estimate as well as a precise answer?
Yes. The calculator is built for quick checks, so round your inputs to a sensible number of significant figures and the result will be just as useful. If you need more precision, keep the same method and add digits to the inputs rather than adjusting the method itself.