Lithium Battery Calculator
Not sure how many watt hours your battery has? Enter the voltage and capacity to work it out. You can also estimate lithium metal content for certain primary lithium cells.
Calculate your battery details
Choose the battery type, enter the details and see your result straight away.
For lithium metal cells, the manufacturer's declared lithium content is the preferred source. The capacity based estimate below is only appropriate for certain primary lithium cells.
Indicative estimate: 0.3 g lithium per Ah per cell. Do not use this approximation for rechargeable lithium ion batteries or as a substitute for verified manufacturer data.
Understanding the results
Watt hours (Wh)
For lithium ion batteries, multiply the nominal voltage by the capacity in amp hours. If the label gives mAh, divide that number by 1,000 first.
Example: 36 V × 15 Ah = 540 Wh.
Lithium metal content
For lithium metal batteries, use verified lithium content from the manufacturer wherever possible. Some primary cell types use an indicative estimate of 0.3 g per Ah, but it is not universal.
For a battery made from several cells, add the lithium content of the cells within that battery.
Lithium battery calculator FAQs
How do I calculate watt hours from volts and Ah?
Multiply the battery's nominal voltage by its amp hour rating. For example, 12 V × 10 Ah = 120 Wh.
How do I convert mAh to Wh?
Divide mAh by 1,000 to get Ah, then multiply by nominal voltage. A 3.7 V battery rated at 5,000 mAh has 18.5 Wh.
What if my battery only shows volts and mAh?
Enter the voltage, choose mAh as the capacity unit and enter the number on the label. The calculator will convert it automatically.
Can I ship a lithium ion battery over 100 Wh?
Some batteries over 100 Wh can be shipped as dangerous goods when the applicable regulations, packaging instructions and carrier requirements are met. Acceptance depends on the transport mode, battery condition and shipment configuration.
How do I calculate lithium metal content?
Use the manufacturer's lithium content per cell and multiply it by the number of cells. For certain primary lithium cells, a preliminary estimate of 0.3 grams per amp hour may be useful, but manufacturer verification is preferred.
Does the calculator tell me whether my battery can fly?
No. Watt hours or lithium content are only part of the assessment. Air transport also depends on classification, packing instruction, state of charge where applicable, testing, packaging, documentation and carrier acceptance.
Can used e-bike batteries be shipped internationally?
Some used e-bike batteries can be shipped when they are in acceptable condition and meet the applicable dangerous goods requirements. We assess the battery details and available freight options before confirming a shipment.
Have a battery to send?
Send us the battery details and destination. We'll help you work out the next step.
Get a Lithium Battery Shipping QuoteDisclaimer: This calculator is for general information only. It does not classify a shipment or confirm compliance with IATA, IMDG, NZS 5433 or any carrier's requirements. Always check the current regulations and manufacturer documentation.