There are no direct interchangeable alternatives for group 24 battery if we speak about dimensions, but if your battery space hasn't strict limits, you can choose a little bigger or smaller battery group. If your battery. If you need 24 Volts, you can connect two group 24 batteries in series to double the voltage. The voltage of a series connection is equal to the sum of the voltages of all its batteries. If one 12V lead-acid battery is. If you need to increase current capacity and reduce charging time, connect batteries in parallel. When group 24 batteries are in parallel, their voltage is equal to the voltage of one.