4s BMS 120a LifePo4 with M6 Threaded Terminals

(3 customer reviews)


  • Comes with M6 Threaded Terminals soldered to the board as shown.
  • BMS For 4 cell, 12v volt Lithium-iron-phosphate DIY batteries
  • 120 amp continuous charge or discharge current
  • Low Temperature Charging cutoff at -1c
  • Fully programmable with IOS app, Android app, or Desktop app
  • User Manual: Click to Download the PDF user manual

End-of-Life Notice

The 4 cell 120a JBD BMS is no longer being produced. When our current stock is sold, no more will be made.

We will be replacing this model with a brand new BMS that has been designed in America (and programmed in Canada) by Overkill Solar.
The new BMS is called The Pathfinder BMS, and we are working around the clock to get it ready for sale. Check back for more info later.

When it is closer to being ready, it will be available for pre-order. Sometime in June 2024, if all goes well.

Out of stock

SKU: 4s120aM6Thread Categories: ,


User Manual: Click here to download the manual (PDF)

BMS For 4 cell, 12v volt Lithium-iron-phosphate DIY batteries.
120 amp continuous charge or discharge current.
Low Temperature Charging cutoff at -1c.
The Apps allow you to monitor SOC (state of charge), Current, Voltage, cell balance, temperature, and more.

Bluetooth Module is included, Balance wires are included, USB module is an additional purchase.
Fully programmable.

Final assembly, testing and calibration is done in Naples, Florida. Units with 8 gauge wires and/or crimped lugs are assembled in Naples,  FL. The BMS is manufactured in China.

To view or change Parameters, there are 3 ways to connect to the BMS. All 3 applications are free.

Click here for Software Downloads and Support Resources.

A great resource for general DIY power education is www.Mobile-Solarpower.com

FYI for experimenters: The BMS communicates with a 5v TTL UART at 9600 baud. It is directly compatible with Arduinos, etc.
We have written a new Arduino library for the BMSs, now available on the downloads page. The beta version allows you to read all the monitoring parameters and switch charge and discharge on/off. Future releases will have full read/write capability. A python library is also in the works.

Additional information

Weight 1 lbs
Dimensions 6 × 4 × 1 in
Wire Size:

10 gauge x 12" (discontinued), M6 Threaded Terminals, 8 gauge x 12" (Standard), 8 gauge x 24" (+$22), No wires (-$8)

SKU 4s120aM6Thread
Product ID 5008147

3 reviews for 4s BMS 120a LifePo4 with M6 Threaded Terminals

  1. Bob Nelson (verified owner)

    Love the bullet proofed BMS. Got my swag dejour of 100 small zip strips that I will use with my battery setup. Now to get an inline 150amp fuse for just incase. Will definitely be ordering again.
    Came fast via priority mail and so far all is well.

  2. Joseph Suchta

    I purchased four of these. They’ve worked great. Never had an issue.

  3. David Gronek

    I purchased two of these two years ago. They work great and are pretty simple to install Follow the directions for setting them up and you’ll have no issues. Customer service was great. I had one question and they got back to me very quickly. Its really my go to app to monitor mybattery status.

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