On theory energy loss can’t be avoided during store. Its proper electrochemistry construction makes the losing unavoidable. Self-discharge is the best-known causation. Generally this has to do with the electrolytic solubility of the positive electrode material or its thermodynamic instability (easy spontaneous decomposition). Self-discharge in rechargeable batteries is particularly high in comparison to primary battery. Furthermore every month a battery self-discharge rate is various depending on the system. It changes in the range of 10-35%. Primary battery self-discharge is lower considerably. At room temperature it may even be below 2%. However, various processes take place in parallel with this which lead to an increase of the battery’s internal resistance during storage. These processes lead to a reduction in load capability. However energy loss is more noticeable at relatively high discharge current.