How To Stack Multiple Batteries
In order to stack multiple batteries, you need to first balance them (meaning they all have nearly the same voltage). The voltage between batteries being stacked must be 1/2 Volt or less. Usually, the easiest way to do this is to simply fully charge the batteries before stacking. When doing this, it’s important to observe that the state of charge is reading 29.0 volts or higher. You can also balance your batteries by checking the voltage of each battery and charging or draining them until they are within 1/2 of a volt.
Once all batteries are fully balanced, they can then be stacked together for use with the power module placed on top. Again, it’s important to remember that until the display meter is programmed to the new capacity and the batteries are fully charged, the display meter will not read an accurate state of charge. You will know the batteries are full if the meter reads 100%, AND the battery voltage is 29.0 or higher.
To program battery capacity:
1 battery = 74 ah
2 batteries = 148 ah
3 batteries = 222 ah
4 batteries = 296 ah
5 batteries = 370 ah