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Protection Circuit Module (PCM) with Equilibrium function for 21 cells (77.7V) Li-Ion Battery Pack at 100A limit (#5421)

Your Price: $256.60, Do not ship to outside of USA.
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Product ID # 5421
Part Number:

 Protection Circuit Module for 21 Cells (77.7V) Pack

This protection circuit is specially designed for 77.7V Li-Ion / polymer Li-Ion Battery pack with 100A discharging rate.  Different than normal PCB, it provides equilibrium function after battery pack is fully charged. PCM will detect each cell's voltage and trim higher voltage down until other cells reach the same voltage level. Therefore, it helps Li-Ion cells have longer service life. Also the PCM will provide the following protections:

  • Prevent 77.7V Li-Ion Battery pack from over charge
  • Balance each cell at Max. 4.20/cell (required voltage tolerance within 0.025V for each cell)
  • Protect 77.7V Li-Ion Battery pack from over discharge (3.0V/cell) 
  • Limit 77.7V Li-Ion Battery pack's discharging current below 100 A (continuous) 
  •  Please click here to download the specification 



  • If you want to use this pcm for a battery that is rated less than 100A drain, you must add additional protection device to protect the battery itself. Such as: proper rated polyswitch.  
  • To achieve balance, each cell in battery pack must has equal voltage within tolerance of 0.2V. When charger LED turn Green, allow 30 minutes for pack to balance before use
  • You must be professional in Li-Ion battery pack to buy the PCM. Misusing PCM may cause battery damage or explode.  We are not responsible for any damage caused by user.

Batteryspace is not responsible for any damage cause by misunderstanding and misuse! Please read the following instruction carefully before assembling. 

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