The configuration of the 18650 battery pack mainly includes the series and parallel connection methods of the batteries, as well as the required number of batteries.
Basic concepts of series and parallel connection
Series connection: Connect the positive terminals of multiple batteries to the negative terminals of another battery to increase the total voltage of the battery pack. For example, when three 18650 batteries are connected in series, the total voltage is 12V (3.7V × 3=11.1V).
Parallel connection: Connect the positive and negative poles of multiple batteries together to increase the total capacity of the battery pack. For example, when three 18650 batteries are connected in parallel, the total capacity is three times the capacity of a single battery (assuming each battery has the same capacity).
Basic parameters of 18650 battery
Nominal voltage: generally 3.7V, with a voltage of 4.2V when fully charged.
Common capacities: ranging from 1800mAh to 3500mAh, with mainstream capacities ranging from 2200mAh to 2600mAh.
Size: Diameter 18mm, length 65mm.
Configuration Example
48V12AH battery pack: requires 78 2000mAh 18650 batteries. The calculation method is: 48V ÷ 3.7V=13S (series number), 12AH ÷ 2AH=6P (parallel number), so the total number of cells is 13S × 6P=78.
12V battery pack: requires 6 18650 batteries. First, connect the three sections in series to form one group, and then connect the two groups in parallel.
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