Yes, you can mix different capacity lithium batteries, whether a normal 12V 100Ah battery or a Lithium server rack battery. There are a few points you need to consider when wiring in. . Figure 2 shows two 12-volt batteries connected in series. In this example the resulting pack voltage is 24 volts. I check each battery regularly with a DC clamp on and current variation between them is apx. For example, linking two 12V/100Ah batteries in series creates a 24V/100Ah system – perfect for solar installations, electric vehicles, and industrial equipment.
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