Six reasons leading to the scrapping of electric vehicle batteries

Due to differences in the types, manufacturing conditions, and methods of use of the plates, the causes of battery failures are ultimately different. To sum up, the failure of lead-acid batteries has the following six situations. 1. Unbalance Most lead-acid batteries are not used alone, but are used together. If one or two of the batteries in each group are behind, it can cause other good ones to be unable to be used normally. This is called unbalanced .　　Second, water loss 　　In the process of battery charging, water electrolysis will occur to produce oxygen and hydrogen, so that water is lost in the form of hydrogen and oxygen, so it is also called gassing. Water plays a very important role in the electrochemical system of the battery. The reduction of the amount of water will reduce the ion activity involved in the reaction, and the reduction of the contact area between sulfuric acid and the lead plate will increase the internal resistance of the battery, increase the polarization, and ultimately lead to the decrease of the battery capacity. . 'Three. Irreversible sulfation' When the battery is over-discharged and stored in a discharged state for a long time, its negative electrode will form a coarse lead sulfate crystal that is difficult to accept charging. This phenomenon is called irreversible sulfation. Slight irreversible sulfation can still be recovered by some methods; in severe cases, the electrode will fail and cannot be charged. Fourth, the electrode plate softened The electrode plate is a material with multiple voids, which has a much larger specific surface area than the electrode plate itself. During the repeated charge and discharge cycles of the battery, the alternating changes of different materials on the electrode plate will cause The void ratio of the plate gradually decreases. In terms of appearance, the surface of the positive plate gradually changes from firmness at the beginning to soft until it becomes a paste. At this time, the decrease in surface area will cause a decrease in battery capacity. High-current charging and discharging and over-discharging will accelerate the softening of the plate.　　5, short-circuit 　　In the circuit, the current does not flow through the electrical appliances, and the two poles of the power supply are directly connected, and the power supply is short-circuited. Because the resistance of the wire is small, the current on the circuit will be very large when the power supply is short-circuited. Such a large current will not be able to withstand the battery or other power sources, and it will cause damage to the power supply. What is more serious is that because the current is too large, the temperature of the wire will rise, which may cause a fire in severe cases.　　6. u200bu200bOpen circuit 　　 means that because a certain part of the circuit is disconnected and the resistance is too large, the current cannot pass through normally, resulting in zero current in the circuit. The voltage across the interruption point is the power supply voltage, which generally does not damage the circuit. If it is possible that the wire is broken, or the electrical appliance (such as the filament in the bulb is broken) is disconnected from the circuit, etc. Prev: Charge the battery of electric car frequently or charge it after it is discharged?