SKU: 92980309110

BMT 4S LITH BATT CHARGE/PROT 40A

$33.65 $37.39
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Description

BMT 4S LITH BATT CHARGE/PROT 40AS 40A Li Ion Lithium Battery 18650 Charger Protection Board Module 18650 Charger Protection Board Module Specifications 4 string 16. 8V 40A lithium battery protection board (comes with recovery function AUTO Recovery) Scope: Nominal voltage of 3. 6V, 3. 7V lithium battery (including 18650,26650, polymer lithium battery) Product Size: 45 * 55 * 3. 4mm (Standard Edition Enhanced), 46 * 60 * 3. 4mm (balanced version) Product weight: 9. 3g (standard

S 40A Li-Ion Lithium Battery 18650 Charger Protection Board Module

18650 Charger Protection Board Module

Specifications

  • 4 string 16.8V 40A lithium battery protection board (comes with recovery function-AUTO Recovery)
  • Scope: Nominal voltage of 3.6V, 3.7V lithium battery (including 18650,26650, polymer lithium battery)
  • Product Size: 45 * 55 * 3.4mm (Standard Edition / Enhanced), 46 * 60 * 3.4mm (balanced version)
  • Product weight: 9.3g (standard / enhanced version), 10.3g (balanced version)
  • Charging voltage: 16.8V - 18.1V
  • Continuous discharge current (upper limit): 40A (if the cooling environment is not good, please reduce the load current use)
  • Continuous charge current (upper limit): 20A
  • Equalization version: suitable for starting current below 80A, power 135W below the drill.

    Project Min. Typ. Max. Units
    Consuming current 12 18 24 uA
    Overcharged protection voltage 4.2 4.25 4.3 V
    Balanced starting voltage 4.17 4.2 4.23 V
    Equilibrium current 95 100 105 mA
    Balanced heating power 1.56 1.72 1.91 W
    Overcharge recovery voltage 4.1 4.15 4.2 V
    Over-discharge protection voltage 2.4 2.5 2.6 V
    Overvoltage protection after over-discharge protection 2.8 3 3.2 V
    Overvoltage protection after over-discharge protection 3.2 3.5 3.8 V
    Over-discharge recovery voltage 2.9 3.2 3.3 V
    Conduction internal resistance 2.5 3 3.5 mQ
    Overcurrent protection current C 70 80 90 A
    Overcurrent delay time 100 150 200 ms
    Continuous operating current 0 40 40 A
    Continuous output power 0 672 672 W
    Ambient temperature -40 25 85 °C

    Troubleshooting:    
    Fault phenomenon Fault check and cause The solution
    Unable to charge Measuring the voltage of 4 groups of batteries. 
    when one of the battery voltages exceeds 4.25V, 
    the protection board will activate overcharge protection.    		 Pair the battery pack well, do not mix 
    the good battery and the bad battery.
    Unable to discharge Measuring the voltage of 4 groups of batteries. 
    when one of the battery voltages is lower than 2.7V, 
    the protection board will activate the over-discharge 
    protection.    		 Pair the battery pack well, do not mix 
    the good battery and the bad battery.
    Charging/discharging 
    failure    		 OV, 4.2V, S.4V, 12.6V, 16.8V miswired Rewire or replace the new board 
    (human failure, no warranty)
    Overcharge/overdischarge 
    failure    		 OV, 4.2V, 8.4V, 12.6V, 16.8V miswired Rewire or replace the new board 
    (human failure, no warranty)
    Discharge protection Check that the battery pack has sufficient discharge 
    capability and check that the load's starting current 
    exceeds the overcurrent protection current of the 
    protection board.    		 Replace the battery pack with a higher 
    discharge capacity, or a protective 
    plate with a larger current 
    (super working range)
    Component soldering There is no connection between one of the components 
    and the PCB pad.    		 Repair welding
    Component welding There is a short circuit between two or more pins of the 
    component.    		 Remove the component and re-weld
    Electrostatic breakdown A In the unpowered state, measure the G, D, and S 
    poles of the MOSFET. If the forward and reverse 
    resistances of any two pins are 0Q, 
    it indicates that it has broken down.    		 Remove the replacement MOS tube
    Electrostatic breakdown B Remove the MOS tube and measure the resistance 
    of the G and D, G and S poles of the MOS tube. 
    If there is a resistance indicating that it has broken 
    down, the resistance should be infinite.    		 Remove the replacement MOS tube

    Package includes:

    1 x Battery Protection Board 

Additional Information

Device Protection Board Module
Type 18650 | Charger Protection
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 92980309110

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4.4 ★★★★★
Based on 15 reviews
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Product Reviews
R
Verified Purchase
Rafael
Charlottesville, US
★★★★★ 5
Elegant Boots
Size: 10.5, Color: Brown
Very Beautiful, confortable, very hight quality, very elegant.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 3, 2025
V
Verified Purchase
Vince1
Birmingham, US
★★★★★ 5
Comfortable
Size: 10 Wide, Color: Cognac
Best chukka I’ve had. Fit and comfort right out of the box.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 9, 2026
F
Verified Purchase
Freddo R
Massapequa, US
★★★★★ 5
Worth the Price!
Size: 8.5 Wide, Color: Brown
It’s really worth my money for this shoes. The style & quality look good! Fitting is perfect & true to size. I’m satisfied w/ my purchase. Many thanks, Amazon.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 15, 2025
G
Verified Purchase
Gary
Houston, US
★★★★★ 4
7 months after purchase
Size: 8.5 Wide, Color: Black
7 months after purchase. Still look good. Very comfortable right out of box. Outside edges of heels chipped away almost right away. Never seen that before. Brittle/ bad choice of rubber or design? Leather upper still looks pretty good with a little polish. Rubber soles wearing very well.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 6, 2025
S
Verified Purchase
Santosh
Dallas, US
★★★★★ 5
Good quality and beautifull
Size: 10, Color: Cognac
i never put an revieuw. but i cam here to leave my revieuw for shis shoe. Florsheim Men's, Rucci Plain Toe Chukka Boot is the best Floesheim shoe i ever had, i was afraid to buy it because i life in south amarica en its expensive. but it amazing, very soft inside and true size. i would defenitly buy an black on. and it not heavy, feels light on the feet. i hope you will have the same experience.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 1, 2026

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