48v 6.4ah 307.84wh Battery + 15a BMS - $97/kWh
The 15a BMS is affordable and perfect to add to this module making it a 2c charge and discharge module. Comes out to just $97/kWh.
These modules come with a 15a BMS. You will have to install the BMS however it is very simple to install. You can see in the 2nd photo how we installed one. The B- and C- already have ring terminals added. You will need 2x M6-1.0 and 1x M5-0.8 bolts. Bolts should be no longer than 1/2". B- (black thick wire) goes to the main negative then C- (blue thick wire) you can use the bolt next to it as you can see in the 2nd photo. The module balance leads can be soldered right to the cell tabs sticking up. There is extra flux and solder on each tab already. Just heat it up and stick the balance leads on there. The board even has labels on there. main negative balance lead (black thin wire) goes to the tab labelled LP0. The wire next to it goes to LP1. Continue in line until the last red wire goes to LP13. Your new negative for charge and discharge will be the blue wire and the positive for charge and discharge is still the main positive of the battery. In the 3rd photo you will see the + and - marked as the new positive and negative after you install the BMS.
Each 48v module will be good for up to 500w of power. You can parallel as many of these as you want to build a nice modular 48v battery. Just make sure all the batteries are the same voltage before connecting in parallel and also when you parallel them, use equal length wires from each module into a distribution busbar to ensure even distribution of current to each module. If you have a 5000w 48v inverter you can parallel 10 of these modules each with their own BMS and run those 10 modules into a busbar that can handle 120 amps.
They come with Panasonic cells inside. 48.1v 6.4ah 307.84wh. You will not find a better deal on 48v batteries with a BMS that have either never cycled or only cycled a few times. Perfect for solar storage as well. These modules have 52 cells inside. Every module tests around full capacity. Since these were used as backup only they likely have never been cycled. The cells are power cells, Sanyo UR18650WX 1600mah cells manufactured by Panasonic which are 25a rated power cells.
The battery module is 8 lbs.
Module size is approximately 13" x 6" x 2.25"
Nominal voltage - 48.1v (3.7v per cell)
Fully charged voltage - 54.6v (4.2v per cell)
Fully discharged voltage - 36.4v (2.8v per cell)
Recommended Max continuous charge - 500 watts (12 amps)
Recommended Max continuous discharge - 500 watts (12 amps)
Note: Do not stack these with weight on the top of the battery.
This BMS can handle up to 15a but we always recommend running BMS units at 80% or less continuous.