In general, the high-type lead-acid battery is best laid out, and the lower-type battery is better vertical. The reason is that the vertical discharge of the battery easily leads to the stratification of the electrolyte inside the battery, and after a long time of placement, the sulfuric acid density of the upper layer becomes thinner. The density of sulphuric acid in the lower layer becomes thicker, so as to form the concentration difference, which forms the internal micro-battery. The existence of the micro-battery leads to the serious self-discharge of the battery and shortens the service life of the battery for a long time. However, the possibility of electrolyte delamination of low-type batteries is much less, and vertical placement will effectively reduce the possibility of leakage of the batteries. Therefore, the low-type batteries should be placed firmly.