Begin with the manufacturer’s limits
Identify the battery chemistry, nominal voltage, capacity, connector, and the equipment it is intended to power. Follow the battery and charger manufacturers’ instructions for the exact products. Similar size or a connector that fits does not establish compatibility.
Do not infer a charging setting from an example on this site. Different chemistries and product types have different requirements. A charging process needs the correct equipment, settings, condition checks, and supervision described by its manufacturer.
Compare energy in the same units
Milliamp-hours describe capacity, but voltage matters when comparing energy. A useful label calculation is watt-hours: nominal volts multiplied by amp-hours. Divide milliamp-hours by 1,000 first.
For example, a pack labeled 14.8 volts and 1,300 mAh has a nominal energy figure of 14.8 × 1.3 = 19.24 Wh. This is a mathematical illustration, not a recommended pack or charger setting. Use the actual nominal voltage on your own battery label.
A bigger number is not a flight-time promise
More nominal energy also comes with physical size, weight, and system considerations. Aircraft efficiency, flying style, conditions, battery condition, and the usable operating range affect the result. A watt-hour calculation cannot tell you how many minutes a particular aircraft will fly.
Compare an appropriate power system as a whole. Do not increase battery voltage or change connectors because a calculator produces a more attractive number.
Condition beats optimism
Inspect batteries and connectors according to the manufacturer’s guidance, especially after impacts. Do not keep using or charging a damaged, swollen, leaking, or otherwise suspect pack. Follow the manufacturer and local waste authority for handling and disposal; do not invent a repair or disposal experiment.
Store and transport batteries using the instructions for their chemistry and products, protecting terminals from short circuits. A careful routine is more valuable than treating the label as a contest.
MAKE IT USEFUL
Your next small job.
Use the energy calculator with a battery label. Record the result as nominal Wh—not a predicted flight time or charging instruction.
Go straight to the source.
These official resources support the next step. Hardware, firmware, and local requirements can differ.