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Li-Ion cells will promote the exploitation of renewable energy sources, playing an important role in helping societies to reach their emissions reduction targets. They do this in three ways, by balancing the mismatch between electricity production and demand, by permitting the use of distributed renewable energy systems, and by providing power backup. However, while Li-Ion cells are characterised by high voltages, high energy/power density and moderate operating life, their performance is quite sensitive to temperature [1]–[3]. Adverse temperature operation leads to capacity fade, faster ageing effect and thermal runaway. Therefore, Li-Ion cells should operate in the range of 25- 40°C. Also, a minimal temperature disuniformity within the cell [3], [4] can avoid localised cell deterioration and battery pack performance defects. Four main Thermal Management Systems (TMS) for Li-Ion cells are reported in literature: air-cooling, liquid- cooling, flow/pool boiling and Phase Change Materials (PCM). Among these, PCMs can be an effective TMS. When used as a passive cooling technique, they are characterised by moderate capital and O&M costs, compactness, high efficiency and low parasitic power consumption [5]. However, when Li-Ion cells are operated continuously at high discharge rates, PCMs could recover only part of their latent heat potential by solidification and this can lead to thermal runaway after a certain number of cycles. Therefore, details on the electricity demand are essential. This research project focuses on the optimisation of Li-Ion cells’ TMS by PCM. Different designs of aluminum- sintered blocks filled with octadecane as PCM are tested to determine the TMS benefits on the Li-Ion cells’ electrical and thermal performance. |
