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14S 48V 40A BMS Li-ion Cell Battery RJXZS Balanced E-bike UK seller UK stock

  • UK Stock, UK seller for rapid delivery. Check out sellers shop for a variety of other DIY electrical and battery essentials

    DISCLAIMER: This item is a sophisticated electronic controller. You will need skill and knowledge to install it and use it. You will need to have done research, some available on YouTube - search "eBike School" and "Jehu Garcia" by example to find out what a bms is, what it does and especially how to install it. Wiring diagrams and how to use the bms are found on this listing. It will not be possible to return this item once opened and used, but most especially due to use or damge caused by negligence or lack of knowledge.
    This bms is for a Lithium-ion battery. Not suitable for a LiFePO4 battery
   14S 48V 40A BMS Li-ion Cell Battery RJXZS Balanced

Item specifics
  • Brand Name:RJXZS
  • Supply Voltage:48v
  • Type:Voltage Regulator
  • Dissipation Power:50
  • Package:TQFP
  • Condition:New
  • is_customized:Yes
  • Operating Temperature:-40-85
  • Model Number:PCM14S0540LIPH14
  • Application:li-ion battey cell

This bms is used for Li-ion battery pack, The BMS charge “C-” 

and discharge port is   "P-"


1) With balance

2) With Balance/Signal Cables;

3) With Temperature switch

4) The BMS charge with discharge port is different;

5) Detection circuit (over-discharge, over-current , and load short circuit)








14S40A Double Two layers alloy Boards, 2 sides of FETs




1. Battery assembly notice before BMS installation:

Each cell must match well before BM installation (Battery internal resistance differences within 5 Milliohm, voltage within 0.03 V , capacity vary within 50 mAh). Lfepo4 cell, voltage between 2.6V~3.5V,Li-ion cell, voltage between 3~4V.

If the cells are full charged,please discharge them to the standard voltage range.Cell first parallel then series.

2. Connection instruction of BMS wires:

(a) Connect B- big short wire to battery general negative end( B-and Discharge port with multi-holes, you can use one large wire to connect one hole or several middle wires to connect each hole.)

(b) Connect signal/Balance wires: remove the balance wires from BMS before you assembly. Start from B-, first wire connect to B-,the second balance B1 wire connect to the first cell positive, B2 connect to second cell positive,balance wires soldering should be according to the order of B-,B1,B2,B3....B14

(c) Make sure all of the wires correct before you plug the connector into BMS:use multi meter to test each neighbouring series voltage ,if not, the BMS will burn.( Li-ion voltage less then 4V,Lifepo4 voltage less than 3.5V)

(d) Test the battery general negative voltage between battery general positive whether equal the total voltage.

(e) Plug the balance wires to BMS(plug low bit to high bit),  Connect wire to “ C-” connect large wire to "P-"   Connect TWO red wires (one same size match with C- for charge,one same size match with P- for discharge) to battery general positive end.  Test discharge total voltage again.

3. Battery charger usage:

Li-ion Battery pack use Li-ion charger voltage: Series x 4.2V

Lifepo4 Battery pack use Lifepo4 charger voltage:Series x 3.6V

Charge current is the battery capacity 0.2C