Discount 70% Off And Free Shipping On Orders Over £45

Discount 70% Off And Free Shipping On Orders Over £45

Building Materials UK Online Sale
Login / Register
Search
0 items £0.00
Menu
Building Materials UK Online Sale
0 items £0.00
  • Shop
-65%
Click to enlarge
Home batteries 4s LiFePO4 120A BMS with balance & temp sensor
Molicel P28A FLAT TOP 18650 High drain battery £5.90 Original price was: £5.90.£2.66Current price is: £2.66.
Back to products
1s 3.7V 5A Li-Ion BMS Protection board £2.95 Original price was: £2.95.£1.33Current price is: £1.33.

4s LiFePO4 120A BMS with balance & temp sensor

£39.75 Original price was: £39.75.£13.91Current price is: £13.91.

4 Items sold in last 18 minutes
  • 30 days easy returns
  • Delivery within 2-5 days
16 People watching this product now!
SKU: UK-7801746456791 Category: batteries
  • Description
Description

4s LiFePO4 120A BMS with balance & temp sensor

 

This BMS is built with Integrated Management solution with up to 120A continuous discharge current for a 4s LiFePO4 nominal 12.8V configurations. It can detect each cell voltage during the discharging and charge phase, but at the same time will optimise & maximise the longevity of your battery pack. Fully charge voltage is 14.4V and has a maximum charge Current of 60A with a very low stand by power consumption.

 

Technical parameters:

  • Model number: BMS4S120A42
  • Chemistry: LiFePO4
  • Configuration: 4s
  • Max Voltage: 14.4V
  • Nominal Voltage: 12.8V
  • Continuous discharge Current: 120A (additional cooling required)
  • Max Charging Current: 60A
  • Overcharge protection: 3.65V per cell
  • Over discharge protection: 2.35V per cell
  • Temperature protection (Discharge max temperature 75 degree Celsius, Charge min temperature -7 degree Celsius)
  • Balancing Current: 100mA
  • Load Short circuit protection
  • Charging port: Same port
  • Dimension: L72 x W55 x H14mm

 Balance wires included.

IMPORTANT:

Ensure that you connect the balance loom to the battery’s cell terminals in the correct voltage sequence. Check that the voltage increases in the expected order on the JST female connector (Black + first Red, + second Red, etc.) BEFORE plugging it into the male connector on the BMS board.

When connecting to your battery, the B- line should be connected first and then the voltage monitoring Balance loom. The very last step is to connect charge/discharge lines. If you want to uninstall the BMS, the order should be reversed. BMS connection order is important, or it will irreparably damage the BMS.  If you have no voltage at the BMS load terminals, then check your wiring and check again.  If the wiring is not the issue, then it’s likely that you’ve tripped under-voltage detection; connect a charger of the correct voltage to the BMS. If there is still no voltage from the BMS and you’re sure your wiring and battery are ok, then the BMS is damaged.

Furthermore, if you see the BMS cutting the load or charge before expected (i.e. before the battery has fallen or risen to overall cut-off voltage for discharge or charge) then your first step is to look for a cell or parallel group of cells exhibiting a divergent voltage.  Trying to spot the defective cell(s) is difficult because as soon as the load is cut or the charger removed, cell voltage rises or falls instantly.  It requires real-time monitoring to diagnose cell defects.

DISCLAIMER:

This BMS will require a competent and knowledgeable person with an electronic background and skills to install and operate. As these are sensitive products, we will only accept returns if its un-opened and un-used. 

Please double check and triple check your wiring, especially the balance/sense wires are correct. Even temporary incorrect wiring may damage this device.

Related products

-65%
Add to cart

3s / 4s Li-Ion 120A BMS with balance & temp sensor Online Hot Sale

batteries
£39.75 Original price was: £39.75.£13.91Current price is: £13.91.
-65%
Add to cart

4s LiFePo4 200A BMS with balance & temp sensor

batteries
£65.50 Original price was: £65.50.£22.92Current price is: £22.92.
-55%
Add to cart

Braun Oral-B replacement Toothbrush Battery 1000mAh Li-ion with Solder tabs

batteries
£8.45 Original price was: £8.45.£3.80Current price is: £3.80.
-55%
Add to cart

Samsung 50E 21700 Li-ion battery with U-Solder tags / tabs

batteries
£9.50 Original price was: £9.50.£4.28Current price is: £4.28.
-55%
Add to cart

Sinowatt 30SP 3000mAh 18650 High drain cell Online Hot Sale

batteries
£6.50 Original price was: £6.50.£2.92Current price is: £2.92.
-55%
Add to cart

Sinowatt 34MP 3350mAh 18650 BUTTON TOP cell

batteries
£6.85 Original price was: £6.85.£3.08Current price is: £3.08.
-55%
Add to cart

Upgraded Braun Oral-B replacement Toothbrush Battery 1000mAh Li-ion with Solder tabs

batteries
£10.50 Original price was: £10.50.£4.72Current price is: £4.72.
-55%
Add to cart

Vapcell B30 20A 3000mAh FLAT TOP 18650 High drain cell Online now

batteries
£6.99 Original price was: £6.99.£3.15Current price is: £3.15.
    NEED HELP?
    • About us
    • Contact Us
    • Track Your Order
    SUPPORT
    • Shipping Policy
    • Returns & Refunds Policy
    • Terms of service
    • Privacy Policy
    • My account
    NEWSLETTER:

    © 2025 build4lessstore.com
    payments
    • Shop
    • Login / Register
    Shopping cart
    Close
    Sign in
    Close

    Lost your password?

    No account yet?

    Create an Account
    Start typing to see products you are looking for.
    Shop
    0 items Cart
    My account