Objectives and problems to be solved:
Batteries have lifetimes between 3 to 15 years depending on application and battery quality. For end users this seems too short, but they are significantly too long to prove the quality of batteries by a non-accelerated lifetime test. Today, acceleration in tests is done by increasing temperature or cycles per day. But these procedures all have the problem, that accelerated tests do not reproduce the real operating conditions of the batteries. The project team of battery industry and research partners aims at a new procedure. Simulation models will be used to determine the lifetime of batteries in specific applications and operating conditions. But simulation models cannot predict the behaviour of the materials just from the first principles. Therefore electro-chemical tests and impedance spectroscopy are performed to calibrate the simulation models for each battery. The different tests focus each on one specific ageing effect on lead batteries. These tests last less than 12 weeks.
Description of work:
Information available on accelerated and non-accelerated ageing tests will be collected and analysed. Batteries from field installations will be analysed to identify the ageing effects of importance. Because of their very complex ageing effects batteries in renewable energy systems will be in the centre of the investigations. Data on typical operating conditions in different applications will be collected for the use in the lifetime simulations. Electro-chemical test procedures will focus each on one specific ageing effect. These specific results for each battery will calibrate the simulation models. Using the results of the specific ageing effects the model will allow the extrapolation to the long-term performance under various operating conditions by superimposition and weighting the different ageing effects. Therefore a detailed battery model which allows the calculation of the physical parameters at every point at any time in the battery is necessary. Standard physico-chemical tests can be done only as post mortem analysis. They can be performed once from a specimen, but do not allow for continuous monitoring of the state-of-health of the battery. Impedance spectroscopy will help to evaluate the progress of ageing continuously and in site during the test. The accelerated ageing test needs validation with non-accelerated tests. Therefore a couple of non-accelerated tests on different battery technologies and operating conditions will be performed.
Expected results and exploitation plans:
The new procedure will be made available for everybody interested in accelerated tests (manufacturers and users) and may be introduced as standard test procedures accepted by both sides, the manufacturer and the user. The results on the procedures will be disseminated through reports in scientific journals, conferences and on a workshop organised by the consortium.
Funding SchemeCSC - Cost-sharing contracts
13108 St.paul Les Durance
19200 Azuqueca De Henares