[Multiple-string compatibility] 120A high-current lithium battery
protection board
3S/4S/5S/6S/7S/8S universal overcharge/over-discharge/short
circuit/over-temperature full protection
Features
Multiple-string intelligent adaptation: 3S-8S battery packs are
compatible with one key, no need to purchase repeatedly, saving
costs.
120A continuous high current: supports stable operation of
high-power equipment such as power tools and energy storage
systems.
Seven-fold safety protection: overcharge, over-discharge,
overcurrent, short circuit, overtemperature, balance, and reverse
connection protection.
Dynamic balancing technology: ±25mV battery cell voltage difference
control, extending battery life by more than 20%.
Application scenarios
Electric vehicles/electric motorcycles: ensure stable power supply
for high-power motors and no downtime when climbing.
Outdoor energy storage system: solar energy storage, RV power
supply safety management and control.
Industrial equipment: long-term protection of AGV cars and drone
battery packs.
Household appliances: emergency power supply, household energy
storage battery safety protection.
Design advantages
Military-grade MOS tube: using Infineon/TI chips, high temperature
resistance of 130℃, stable and no board burnout.
Intelligent sleep function: standby current <10μA, automatic
power saving when idle.
Minimalist wiring design: gold-plated interface anti-oxidation,
support XT90/Anderson fast connector.
Anti-interference shell: aluminum alloy heat dissipation +
insulation coating, adapt to complex electromagnetic environment
User pain point solution
"Worried about incompatibility of different battery pack models?"
→ Adaptive 3S-8S, no need to replace the protection board, one
board for multiple uses.
"Severe heat generation under high current?"
→ Double-sided heat dissipation silicone + temperature protection,
automatically cut off output at 85℃.
"Poor balancing function leads to rapid battery attenuation?"
→ Dynamic balancing technology, voltage difference <0.03V,
extending the cycle life of the battery cell.
Installation Guide
Three-step quick installation:
Confirm the number of battery pack strings (such as 7S requires 7
wires)
Connect B- (total negative pole) and P- (output negative pole)
Connect the positive pole detection wires of each battery cell
(B1-B8)
Note: Reverse connection is strictly prohibited! Use a multimeter
to verify the voltage before first use.
Warranty and Service
One-year warranty: Free replacement for non-human damage (including
overcurrent burnout cases).
Technical support: Provide wiring diagram customization and
parameter debugging remote guidance.
Accessory set: Optional silicone wire, heat shrink tube, and
insulating gasket of the same style.
Technical Parameters
| | Item type | Parameters |
| 1 | Parameter Overview | Product Model | EK-BM3R8S120A |
| Product Size(mm) | L95*W68*T15 |
| Product Weight(kg) | 0.25 |
| Product Material | FR-4 / Lead-free spray tin |
| Applicable battery type | Lifepo4 | Li-ion | Lto | SIB |
| Applicable battery string | 3S-8S | 3S-8S | 3S-8S | 3S-8S |
| Rated discharge current | 120A | 120A | 120A | 120A |
| Peak starting current | 300A | 300A | 300A | 300A |
| | Item type | Trigger
(time) | Trigger
(time) | Trigger
(time) | Trigger
(time) | Trigger
(time) | Trigger
(time) | Trigger
(time) | Trigger
(time) |
| 2 | Charging protection | Overvoltage protection voltage value | 3.65V/1S | 3.50V/1S | 4.25V/1S | 4.05V/1S | 2.85V/1S | 2.75V/1S | 3.95V/1S | 3.80V/1S |
| Balanced phase difference voltage value | Trigger voltage difference 30mV / trigger time 0.5S / balance time
10S cycle |
| Balanced voltage value | 3.45V | 3.70V | 2.50V | 3.10V |
| Overcurrent value | 120A/2S, disconnect charger to recover |
| Low temperature value | Charge over-temperature protection 60℃/2S / Release 55℃/2S |
| Overtemperature value | Charging low temperature protection -5℃/2S / Release 0℃/2S |
| 3 | Discharge protection | Undervoltage protection voltage value | 2.30V/1S | 2.70V/1S | 2.75V/1S | 3.0V/1S | 1.70V/1S | 1.80V/1S | 1.50V/1S | 2.00V/1S |
| ①Overcurrent protection value | 150A/2S, disconnect load or activate charging |
| ②Overcurrent protection value | 250A/0.5S, disconnect load or activate charging |
| Short circuit protection value | 500A/128uS, disconnect load or charge activated |
| Low temperature value | Discharge over-temperature protection 65℃/2S, release 60℃/2S |
| Overtemperature value | Discharge low temperature protection -20℃/2S, release -10℃/2S |
| 4 | Others | Standby current consumption | 25uA |
| Motherboard lock voltage | / |
Size $ Packing List
Package included:
1 * BMS with heatsink
1 * NTC Terminal Cable
1 * Switch Cable
1 * Terminal Cable
6 * Terminal Lugs
6 * M5 Screws
Wire Diagram
Wiring precautions:
1. Installing the protective board requires a certain amount of
technical electronic knowledge.
2. When wiring, first connect the B- wire at the soldering pad
position to the total negative terminal of the battery (the B- wire
should be soldered to a short and thick wire) and solder the wired
terminal to the battery pack first, and then insert the protective
plate.
3. The connection between the battery terminal B- and the
protection board terminal B- should be short and thick, otherwise
it will cause the protection board to charge and discharge in
advance and malfunction.
4. You need to use thick wires when wiring P+/P-. Wires that are
too thin and too long will burn the board!
FAQ
Q1. Why did we choose you?
* We can provide you with efficient after-sales service, with more
than 10 years of strong technical support.
* Products have passed FCC, CE, ROHS and other international
standards certification.
* We can provide you with factory price, Welcome you to visit our
factory and production process.
Q2. What is your product range (type)?
*We mainly do battery management systems in the fields of power
batteries, energy storage batteries and consumer batteries.
*Mainly used for LFP, Li-ino and LTO batteries.
Q3: How do I know which kind of material & type my battery is ?
*Please look the battery body, If the normal voltage of your
battery shows 3.2V, The battery is LiFePo4.
*If the normal voltage of your battery shows 3.6V or 3.7V, the
battery is Li-ion or Lto battery.
Q4. Do you have minimum order requirements?
Can it be customized? What is the lead time for samples and
batches?
*Our minimum order quantity is 1 piece, ODM customization is
available.
* 1~3 days delivery of existing samples, 3~10 days delivery of
customized samples.
Q5: What if i can't use it?
*Regular products have instructional videos, We can also support
online video call guidance from engineers.
Q6. What are your terms of payment?
*We accept wire transfer and cash payment, all negotiable. Payment
method :visa, mastercard, T/T, PayPal, APPLE_PAY, GOOGLE_PAY,
GC_REAL_TIME_BANK_TRANSFER, RMB
Q7. How do you guarantee the quality?
* All our products are subjected to professional laboratory 100%
testing, as well as repeated aging tests.
* Obtained FCC, CE, ROHS and other international standard
certification.
* Provide 3 years after-sales warranty service. Free spare units
for replace in 3 years.
Q8. How to choose a BMS suitable for our battery?
*Depending on the voltage and current that matches your battery,
you can consult our customer service and we will provide it for you
equipped with the most suitable battery management system.
Q9. How can i contact you?
*We have 7x24 hours online service, Please leave us a message
online.
*You can also contact us by Email, WhatsApp, WeChat, etc(see
below). We are so glad to work with you.
Noted: We are source manufacturer, We have own brand for "EnerKey",We can customized product as your requirement(Voltage, Wire,Etc) .
We can provide you competitive price in the market if you have bulk
order, Please don't hesitate to contact us.
Mobile & WhatsApp & Wechat: +86 15387469240; Email: kiwi@enerkey.cn
