How to Connect Batteries in Parallel?
2 Answers
How to connect batteries in parallel: First, clearly identify the positive and negative terminals of both batteries. If you need to connect them in parallel, connect the positive terminals of both batteries together, and then connect the negative terminals together. This achieves the parallel connection of the two batteries. The characteristics of parallel-connected lithium batteries are: voltage remains unchanged, internal resistance is reduced, the battery capacity is the sum of the two batteries, and the power supply time is extended. The core content of parallel charging is the magnitude of the parallel current and its effect. According to parallel circuit theory, the current in the main circuit equals the sum of the currents in the individual branches. Therefore, to achieve the same charging efficiency as a single battery, the charging current should be the sum of the currents of the n lithium batteries combined into the battery pack. According to Ohm's Law formula I=U/R, this design is reasonable. However, the internal resistance of parallel-connected batteries also changes. According to the parallel internal resistance formula, the total internal resistance of two parallel-connected lithium batteries equals the product of their internal resistances divided by the sum of their internal resistances. It decreases as the number of parallel batteries increases. Therefore, it is possible to achieve efficient parallel charging of lithium batteries with a current less than the sum of the currents of n parallel-connected lithium batteries.
Connecting batteries in parallel is actually quite simple. I'm just an average car owner who enjoys tinkering with small modifications. First, securely place both batteries, making sure no metal objects touch the terminals to avoid short circuits. Use thick cables to tightly connect the positive to positive and negative to negative terminals—avoid thin wires as they can overheat and burn out. Just ensure the voltages match, so the combined capacity lasts longer, like powering lights longer during camping. But remember to turn off all vehicle electronics before starting, wear gloves to prevent shocks, and check that the connections are secure after wiring—give them a shake to test for looseness. Regularly check battery health; mixing old and new batteries will drain power too quickly, so replace them as needed.
