The objective of the Project is to develop a low cost lead-acid battery solution for hybrid electric vehicles based on a novel, individual, spirally wound valve-regulated lead-acid 2V cell optimized for this application. This cell will be used as a building block for the development of a complete battery pack that is managed at the cell level. Following bench testing, this battery pack will be thoroughly evaluated by substituting it for the Nickel/Metal Hydride pack in a Honda Insight
A paper given at the Future Car Congress in June 2002 covered the first half of the 3-year project and described work carried out in the following areas:
Development of cell and battery testing facilities.
The design and development of the prototype double-ended cell.
The development of the battery pack specification and pack design.
The development of the battery management system.
It also gave details of the test results obtained on the demonstration vehicle with its original NiMH battery.
Arising from these tests, there was discussion of the merits of bench testing with a cycle derived from ‘real vehicle’ data as compared with the PNGV or Eucar power assist life cycle tests.
This follow-up paper gives details of further cell development to overcome problems associated with operation in partial state of charge conditions as well as the results of testing these cells in packs to the special Rholab test profile described above. Following this work, the cells are being incorporated into 36V modules including full battery management and cell conditioning features. Results of the bench testing of these modules will be described and early results should be available from testing the full 144V battery in the Honda Insight.