• 130 N. West Street Crown Point, Indiana 46307
  • Toll Free:   866 894-7337
    219-644-3231

Hybrid battery reconditioning and cell balancing class

Home :: Hybrid Vehicles :: Hybrid battery reconditioning and cell balancing class

Hands-on hybrid electric vehicle battery course

The 2-day nickel metal hydride (NiMH) hybrid battery course demonstrates split current charge-discharge cycling, internal resistance measurements and hybrid battery balancing. No prior knowledge of hybrid batteries is required. The hands-on experience includes use of the EVc-30 hybrid vehicle battery reconditioning unit. Anyone can learn!

Hybrid battery short course (2-day) schedules:

Indiana (35 miles from Chicago)

NuVant Systems Inc.
130 N. West Street

Crown Point, IN 46307

Massachusetts

Northeastern University
360 Huntington Avenue

Boston, MA 02215

May 24-25 May 24-25
June 7-8 June 7-8
June 14-15 June 14-15
June 28-29 June 28-29
July 9-10 July 9-10

Register now!

Course fee: $500/person

Limit: 8 attendees per course

Course fees are rebated with EVc purchase (one company can have multiple rebates).


Call 219-644-3231 for class registration help.


Day 1:  8:30 AM – 4:30 PM

Day 2:  8:30 AM – 4:30 PM


Registration includes

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

Hybrid battery 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.

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

Battery-sorting software module
Battery-sorting software module

 

Background

Hybrid battery packs have 28 to 40 NiMH modules assembled in series. A Prius type prismatic module consists of six individual NiMH cells (1.2 V each) assembled in series. Detailed specifications for these modules are available.  

7.2 V hybrid battery prismatic module with individual cell marked 1 – 6

 


28 prismatic modules with a series nominal 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 undergoes structural changes that effectively reduces amp hour (Ah) capacity. This reversible failure mode (“memory effect”)  takes modules out-of-balance with neighboring modules, especially those that are near the pack center. Out-of-balance modules can undergo voltage reversal during discharge. Voltage reversal at the anode and cathode permanently damages the module.  High-rate charging generates gaseous oxygen at the positive electrode that can pressurize and rupture the module casing.   Modules, reconditioned by a series of deep charge-discharge cycles with tapered currents, will recover lost capacity and have an extended lifetime.  Overheating of hybrid batteries causes venting of vaporized electrolyte water. This permanent failure mode increases the internal resistance of the module. Such  modules substantially increase reconditioning time. Modules suffering from permanent failure modes are identified and removed before full reconditioning.   

 

Syllabus

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

Course Fees:  $500/person (8 person maximum)