12 V lithium ion starter batteries

Inhalt:
The research focuses on the development of 12 V lithium-ion starter batteries for cold cranking. Electric Double Layer and lithium capacitors were connected in parallel to the lithium-ion battery to improve the power capability at low temperature. For controlling voltage, current and temperature of the cells, a Battery Management System was developed. Finally, lots of combinations were tested by applying cold cranking profiles at -28 °C. The goal was to find the best combinations that, fulfilling all the requirements, and saving weight, space and costs. This technology guarantees a longer life of the battery. The results show that the lithium capacitors failed at low temperature and only the Electrochemical Double Layer capacitors helped the lithium-ion cells to perform the cold cranking tests successfully. Lithium titanate cells proved good cold cranking performance, even without capacitors.