The main reasons for the reduced battery capacity and the short standby time are as follows:

The main reasons for the decrease of battery capacity are the following reasons: one: shell cracks or sealant cracks Cracks will cause electrolyte leakage and lower the liquid level. If there is a slight crack on the inner wall, connect the two single cells to reduce the voltage. The main reason for the cracks is that the screws of the battery holder are too tight; the knock is too strong; the exhaust hole is blocked and the gas cannot be released, causing the pressure of the single battery to be too high; the cracks freeze in winter; and the driving vibration is too large.

Reason 2: Self-discharge The phenomenon of gradual loss of electric energy without using a battery with sufficient power is called self-discharge. Self-release is inevitable. Under normal circumstances, the daily discharge rate should not exceed 0.35%-0.5%.

The main reason for 　　 self-discharge:

　　 (1) There are impurities in the plate or electrolyte. The potential difference between the impurities and the plates or between different impurities is generated, thereby forming a local battery. The circuit is formed by electrolyte, which generates a local current to discharge the battery.

　　 (2) The diaphragm ruptured, causing a short circuit between the positive and negative plates.

　　 (3) There is electrolyte or water on the surface of the battery shell, and the electrolyte or water becomes a conductor between the two poles to discharge the battery.

　　 (4) The active material falls off too much and deposits on the bottom of the battery, making the electrode plate shorter and causing discharge. In order to reduce self-discharge, in addition to battery manufacturing materials that should be as pure as possible, the surface of the housing and the pile head must always be kept clean during use, and the electrolyte to be filled must be chemically pure sulfuric acid and distilled water.

　　 Reason 3: The active material of the plate falls off During the normal use and charge and discharge of the battery, the volume of the active material in the electrode plate continuously expands and shrinks, which will cause the active material to slowly fall off. If used improperly, the active material will quickly fall off in large quantities, causing a short circuit of the plates. The main reason for the active material to fall off is excessive current or high temperature during charging, and frequent overcharging. Excessive current during discharging (such as too long connection time of the starter motor) will cause the plate to arch (because the active material of the plate participates in the chemical reaction in a different way, resulting in a different volume change of the plate), it will also cause the active material to fall off.

　　 Reason four: sheet vulcanization. Plate vulcanization is white coarse-crystalline lead sulfate that gradually forms on the surface of the plate. It is difficult to dissolve in the electrolyte, and it is not easy to react with the electrolyte during charging, thereby reducing the active material. In addition, the coarse particles of lead sulfate block the pores of the electrode plate, making it difficult for the electrolyte to penetrate, increasing the internal resistance, reducing the active material in the electrode plate participating in the reaction, and reducing the battery capacity.

The reasons for the vulcanization of the sheet are as follows:

　　 (1) The battery has been in a fully discharged or semi-discharged state for a long time. Due to temperature changes, such as high temperature T, part of the lead sulfate dissolves into the electrolyte on the electrode plate. When the temperature drops, the lead sulfate dissolved in the electrolyte will re-precipitate, recrystallize, and form coarse crystals that sink into the electrode plate.

　　 (2) If the liquid level of the battery is lowered, the upper edge of the board will be exposed and oxidized by the air. Then, in the bumps of the mechanical transmission, the oxidized part will contact the electrolyte and produce coarse-grained sulfuric acid Lead vulcanizes the upper part of the board.

　　 (3) Due to the high specific gravity of the electrolyte, high discharge current, high temperature, the chemical reaction intensifies, the resulting lead sulfate is quickly deposited on the plate, which also promotes vulcanization. In order to prevent the plate from being vulcanized, Power Kingdom batteries should maintain a sufficient power state, the electrolyte should submerge the upper edge of the plate, and the specific gravity of the electrolyte should be correctly selected according to different regions and seasons.