The C-rate is a measure of the rate at which a battery is discharged or charged relative to its maximum capacity. A 1C rate means the battery is discharged or charged in 1 hour. A 2C rate means it's discharged or charged in 30 minutes, and a 0.5C rate means it would take 2 hours. This calculator helps you determine the C-rate based on your battery's capacity and the current flowing through it, or vice versa.
Calculate Current from C-Rate
function calculateCRate() {
var capacity = parseFloat(document.getElementById("batteryCapacity").value);
var current = parseFloat(document.getElementById("current").value);
var resultDiv = document.getElementById("result");
var cRateInput = document.getElementById("cRate");
if (isNaN(capacity) || isNaN(current) || capacity <= 0) {
resultDiv.innerHTML = "Please enter valid numbers for Battery Capacity and Current. Capacity must be greater than 0.";
cRateInput.value = "";
return;
}
var cRate = current / capacity;
cRateInput.value = cRate.toFixed(2) + "C";
resultDiv.innerHTML = "The calculated C-rate is " + cRate.toFixed(2) + "C.";
}
function calculateCurrent() {
var desiredCRate = parseFloat(document.getElementById("cRateFromCurrent").value);
var capacity = parseFloat(document.getElementById("batteryCapacityForCurrent").value);
var resultDiv = document.getElementById("result");
var calculatedCurrentInput = document.getElementById("calculatedCurrent");
if (isNaN(desiredCRate) || isNaN(capacity) || capacity <= 0 || desiredCRate < 0) {
resultDiv.innerHTML = "Please enter valid numbers for Desired C-Rate and Battery Capacity. Capacity must be greater than 0. C-Rate cannot be negative.";
calculatedCurrentInput.value = "";
return;
}
var current = desiredCRate * capacity;
calculatedCurrentInput.value = current.toFixed(0) + " mA";
resultDiv.innerHTML = "To achieve a " + desiredCRate + "C rate with a " + capacity + "mAh battery, you need a current of " + current.toFixed(0) + "mA.";
}
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