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I'm trying to make a lithium ion battery pack It needs to be a 7.4v 74wh the battery's I was thinking about using are 7.4 2000mAh how many 0f these will I need to hit the 74wh mark, or is this even something I have to worry about. It's for a metal detector I'm wanting to build cause a replacement is almost 500 dollars but can put one together for around 100 to 150 any help on this matter will be greatly appreciated . |
1 day, 1 hour ago |
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Wh, Watt-hour, is an amount of energy. If you get less, the battery will simply "works" for a shorter time. Energy = Voltage * Current * TimeOfUse 74 Wh = n (batteries) * 7.4 V * 2 ( Amp * hour) gives n=5. One crucial point which matters and that you didn't mention is the current (amperage) that your device needs. Lithium batteries have a limit of the maximum current they can deliver safely, and if the required current exceeds it, you need a current regulator of some kind for the batteries which, other than knowing that it is required, is not in my domain of competence. |
3 hours, 25 minutes ago |
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