• 130 N. West Street Crown Point, Indiana 46307
  • Toll Free:   866 894-7337

Hands-on hybrid vehicle battery reconditioning and balancing workshop

Home :: Hybrid Vehicles :: Hands-on hybrid vehicle battery reconditioning and balancing workshop




Hands-on battery module balancing course


Short course (2-days) schedules:


NuVant Systems Inc.
130 N. West Street

Crown Point, IN 46307



Northeastern University
360 Huntington Avenue

Boston, MA 02215



Holiday Inn
Austin Town Lake
20 N. IH-35
Austin, TX 78701

Feb. 21-22
Mar. 6-7

Mar. 13-14
Mar. 15-16
Mar. 8-9
Mar. 15-16
Mar. 22-23
Feb. 21-22
Feb. 23-24
Register now! Register now! Register now!

Course fee: $250/person 

Limit: 8 attendees per course

Short course fee is rebated with EVc purchase (one company can have multiple rebates). 

Call 219-644-3231 for registration help.

Day 1:  8:30 AM – 4:30 PM

Day 2:  8:30 AM – 4:30 PM

 Click images to enlarge

 "Out of balance" Ford Escape battery pack

Ford Escape “out-of-balance” battery pack

 Ford Escape reconditioned battery pack

Ford Escape reconditioned battery pack

EVc-30 connected to a 28 module Toyota Prius pack

EVc-30 hybrid vehicle battery reconditioning unit

Battery-sorting software module

Battery-sorting software module

This course teaches hybrid electric vehicle (HEV) battery safety and reconditioning. The focus is cylindrical (Honda, Ford Escape) and prismatic (Toyota, Camry, etc.) nickel metal hydride (NiMH) modules.

Course Benefits

  • Experienced instructors provide in-depth knowledge on hybrid battery cycling, reconditioning and safety issues.
  • Real time demonstration of charge-discharge cycling and battery internal resistance measurements.
  • Learn to identify bad modules prior to reconditioning
  • Work the database for inventory maintenance and pack assembly.
  • The dangers of over-charging and over-discharging.


HEV battery packs have 28 to 40 nickel metal hydride (NiMH) modules assembled in series. A module comprises six individual NiMH cells (1.2 V each) assembled in series. Detailed specifications for these modules are available.  
7.2 V prismatic module with individual cell marked 1 – 6

28 prismatic modules with a series voltage of 202 V

NiMH modules undergo shallow depth-of-discharge (less than 10%) because they are used for power assist, not electric drive.  Unused electrode material develops a resistive barrier that reduces amp hour (Ah) capacity. This reversible failure mode (“memory effect”)  causes modules to become out-of-balance with neighboring modules, especially those that are near the pack center.  Out-of-balance modules can undergo cell voltage reversal during discharge, which results in permanent damage.  During a charge cycle, excessive oxygen evolution can pressurize and rupture the module casing.  Modules must be balanced by a series of deep charge-discharge cycles: The life of “failed” module can then be recovered and extended.

Module overheating causes venting of battery electrolyte water.  This irreversible failure mode permanently increases the module internal resistance. High resistant  modules must be removed: They substantially increase reconditioning time. Modules with reversible failure modes must be separated from those with irreversible failure modes before reconditioning.   

About the course

This 2-day course introduces NiMH batteries  and provides demonstration of split current charge-discharge cycling, internal resistance measurement, and battery pack module balancing.  The course assumes no prior knowledge of batteries.  Anyone can learn! 

Course Fees:  $250/person (8 person maximum)


Registration includes

  • Course work materials
  • Continental breakfast, snacks & coffee breaks.  Lunch on your own.
  • Use of NuVant EVc units for charge-discharge and internal resistance measurements.



  • Lectures
    • Prismatic battery pack structure
      • cell (1.2 V)
      • module (7.2 V)
      • pack (202 V)
    • Terminology
      • C-rate
      • Recombination
      • Memory effect
      • Charge-discharge protocols
      • Internal resistance
      • Capacity
      • Cut-off voltage
      • Split current cycling