A When you design to connect multiple batteries in parallel, please keep the length of ALL cables consistent (from the positive end to the negative end). Battery cables should be appropriately gauge to handle the expected load. Keep the connection tight by using the appropriate number of washers to allow for as much as possible thread engagement between the terminal, cable lugs, and busbars, without bottoming out the terminal bolt. And it is best to use flexible busbars or dedicated cables to connect batteries together.
Note: DO NOT connect batteries with different chemistries.
Please use batteries of the same voltage and capacity for parallel expansion. For example, this lithium ion battery is a 12V 100ah battery, please also use the lithium battery with specifications are 12V 100ah for parallel expansion.
For more question or technical supporting needed, please contact us freely!