As solar power system owners increasingly look to cut ties with the mains grid; battery lifespan becomes an important issue when shopping for a home energy storage solution.
The BPT-S 5 Hybrid from Bosch is a combined energy management, inverter and battery system. The lithium ion batteries in the system, based on nickel-cobalt-aluminium technology (NCA), have a storage capacity ranging from 4.4 to 13.2 kWh, depending on the model.
Ageing tests on the BPT-S 5 Hybrid were recently carried out by the independent Institute for Power Electronics and Electrical Drives (ISEA), RWTH Aachen University and the Centre for Solar Energy and Hydrogen Research Baden-Württemberg (ZSW).
The tests put the batteries under extreme loads; the equivalent of 10,000 full cycles over a period of five years at a 60% discharge depth. In calendar ageing tests at 25 °C over four years, the battery cells did not demonstrate any significant signs of ageing. In an accelerated ageing test where the cells were heated to 55 °C, the batteries lost only 10% of their original capacity over a period of four years.
“These tests enable us to prove that we are not only able to keep our promise in terms of the durability of our batteries but also that we can clearly surpass that promise,” said Dr. Armin Schmiegel, Portfolio Manager for Innovation at Bosch Power Tec.
But what do these results mean over a longer term?
“By extrapolating the results gathered until now, our tests show that these types of cell can achieve a service life of up to 36 years. This exceeds the average market service life by more than 150%,” says Ghada Merei, M.Sc., a researcher at the ISEA institute.
The BPT-S 5 Hybrid is now available in Australia via Energy Matters’ sister company, Apollo Energy. For further information on the system, contact Apollo Energy on 1300 855 484 (local call from anywhere in Australia).
