Center for Electric Car and Energy Conversion

Battery Evaluation Laboratory

The UMASS Lowell Battery Evaluation Laboratory has a complete battery test system. The equipment is designed to test single cells or entire battery modules ranging from 2 to 12 Volts at 1mA to 320 Amps. Stand-alone and conputer-controlled sources and loads are included. The current regulators are capable of current sinking or sourcing and can change from charge to discharge mode instantaneously. Both continuous and pulse charging and discharging algorithms using active loads can be implemented by the data aquisition and control system. The data acquisition and control system consists of the following:

  • 38 channel A/D converter
  • 8 channel D/A converter
  • 24 digital input/outputs

The following tests can be conducted:

  • Capacity Measurement
  • Round Trip Efficiency
  • DC Impedance Test
  • AC Impedance Testing
  • Battery Modeling
  • Battery Abuse Test
  • High Rate Charging and Discharging using Parallel Controllers
  • Life Cycle and Rapid Aging Test
  • Realistic Electric Vehicle Road Test - Batteries involved in the realistic road test are charged and discharged according to data taken by a data acquisition system installed on board an electric vehicle. Battery voltage is monitored to determine whether it remains within the rated operating range of the battery and the vehicle.

The Off Board Electric Vehicle Battery Management System, currently being fabricated, consists of 24 controllers of the type previously described and is used to measure individual battery parameters and to balance individual batteries within a pack. The system is computer controlled and can be programmed to automatically rejuvenate batteries in an electric vehicle, charge and discharge individual batteries in a pack, and protect each battery from overdischarge and overcharge. In addition, this system can accurately measure battery impedence to detect bad batteries. The following measurements can be performed on batteries of any chemistry:

  • Module voltage measurement
  • Module impedance measurement
  • Module or battery pack temperature measurement
  • Module discharge and charge capability

The Acquired data is used to calculate the following:

  • Battery capacity
  • Battery round trip efficiency
  • Individual battery module relative condition
  • Battery model parameters
  • Charger efficiency
  • Charger algorithm

The lab is also equipped with four temperature control chambers. Two of these chambers are large refrigerators which can accomodate larger-sized batteries, such as those from an electric car. Our medium-sized unit can accomodate one battery and provides a wide temperature range of -75 to 175 centigrade. The smallest unit accomodates small batteries such as D-cells and provides precision temperature control using solid-state Peltier effect thermoelectric heater/cooler circuits.

Courses Offered

  • Power Electronics
  • Capstone Projects
  • Electric Vehicle Technology

Research Activities
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