Case Studies

Battery Pack Monitor System for Environmental Testing

Quality Control
Posted in Automotive, Battery Pack Test Systems, Energy and Utilities, Green Technology, LabVIEW, Test & Measurement Automation, Test Stand

Summary

DMC developed a cost-effective, fully automated, and portable testing system designed specifically for monitoring large battery packs through environmental, cycling, and endurance testing.  The system design and core software are based on the DMC Battery Test Platform.

Large battery packs used for Energy Storage Systems (ESS) in Hybrid-Electric Vehicle (HEV), Electric Vehicle (EV), and Plug-In Electric Vehicle (PHEV) electric drive systems are required to undergo extensive environmental and endurance tests.  Ensuring the battery packs operate as designed through these tests requires (1) active simulation of HEV and EV sensor and data environments, (2) continuous and live monitoring and analysis of analog and digital outputs from the packs, and (3) a way to manage and visualize the volumes of recorded data.

Battery Test Stand

Test Stand

Post Test Data Analysis

Data Viewer

Solution

DMC has developed a modular Battery Test Platform specifically designed for testing entire battery packs, sub-modules, and BMS systems for HEV and EV companies, suppliers, and third party testing facilities.  For this project, DMC leveraged the Battery Test Platform to produce a more cost-effective automated test system specifically designed for monitoring large battery packs through environmental, cycling, and endurance testing.

Specific requirements for this system were as follows:

  • Simultaneous testing of 3 battery packs in parallel from a single test stand.
  • Use of cost-effective hardware and design strategies, while maintaining hi-end performance.
  • Live monitoring of over-voltage and under-voltage protection analog output signals.
  • In-rush, parasitic, sleep, and wake current monitoring.
  • Cell voltage and stack voltage accuracy measurements.
  • Simulation of external current, voltage, and temperature sensor inputs to pack.
  • Temperature sensor accuracy measurements.
  • CAN communications performance.
  • Safety system, isolation, and fault condition recognition.
  • Integration of a simple graphical user interface for post-test viewing and analysis of data files.

This test system was built using DMC’s modular Battery Test Platform, incorporating proven software and hardware architectures, along with flexible and reliable subsystem components and instruments, to produce a customized test stand completely tailored to the end users' specifications.  The DMC Battery Test Platform is built around high quality off-the-shelf hardware assembled from a variety of vendors, including National Instruments (NI), Pickering Interfaces, Measurement Computing, Lambda-TDK, and Agilent, among others.  Selection of individual instruments in the DMC system is based completely on required performance, not allegiance to a single hardware vendor.  This strict attention to specifications and performance provides DMC battery test system users with nothing less than best in class performance.

>> For more information on EV Battery Pack and BMS Testing see this DMC White Paper.

Customer Benefits

  • Compact:  Single automated test stand for simultaneous and parallel monitoring of 3 packs.
  • Portable:  Tester is contained in a man portable, 20U high 19" rack enclosure.
  • Precise:  High precision simulated voltage, current, and temperature inputs.
  • Dynamic:  Live capture of complete pack data set under real-world conditions.
  • Flexible:  Complex sequences of test and grading conditions can be setup quickly.
  • Smart:  Standalone, graphical test data analysis program makes sifting through gigabytes of recorded data as simple as using your home DVR.

Technologies

  • NI LabVIEW Development Environment, NI-CAN, NI-DAQmx.
  • NI PCI Dual port CAN cards: software selectable CAN transceiver (HS, LS, 1-wire).
  • NI USB DAQ Modules:  Cost effective Analog and Digital I/O.
  • Dell Dual-Core WinXP system controller.
  • Agilent 7 ½ digit precision Digital Multi-Meter (DMM).
  • Agilent high voltage, programmable DC power supplies.
  • Measurement Computing USB relay modules.
  • Lambda-TDK low voltage, programmable DC power supplies.