Battery Module Notes

There are 22 battery module monitoring boards inside the kiev pack, one each for the 4-cells-per-module known as the LEV50-4 modules.  Two modules are ganged together to form an 8-cell group referred to in the FSM as a cell monitoring unit CMU.

These circuit boards have a battery module monitoring chip that measures and reports the voltage of each cell, provides OV and UV notification, and has provision to passively bleed off individual cells at a low current level (~40-80mA) thru internal mosfets or at a higher level (~160 mA) by driving external mosfet bleed circuits.  The balancing is commanded from the master BMS control unit located under the rear seat.

Thermistors are located on three of the flex tab circuit boards as seen in the picture.  This is where the temperature measurement is made that is reported in the MUT and via CanIon.   Those signals are read by the microcontroller directly.

BMU_board

A diagram showing the cell numbering as used by the MUT and as displayed by the CanIon app was drawn after seeing the inside of a pack with the buss bar layout and routing.  The numbering appears not to be sequential due to the different scheme used by the monitoring IC which starts counting at the most negative cell in a module, and the MUT convention which starts at the most positive cell in a module.

 

pack_numbering

 

 

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