Different capacities of lithium batteries can be connected in parallel?

In the process of parallel connection of lithium batteries, the key is to ensure the consistency of battery parameters, which includes capacity, open circuit voltage and internal resistance. Only if these parameters are similar, the batteries can be connected in parallel, and in order to be safe, it is necessary to add a protection plate. In the case of multiple batteries in parallel, if one of the batteries has a lower capacity and the other parameters are the same, this can cause some potential problems.

During the charging process, if the batteries connected in parallel are not equipped with protection plates, a charger with a limiting voltage of 4.2V must be used to prevent the lithium battery from being overcharged and causing an explosion. Even if the protection plate is installed, since the battery with low capacity will be fully charged first, a long period of overcharging will lead to an increase in its internal electrolyte and the occurrence of side reactions, which in turn will lead to an explosion.

Battery leakage occurs. In the discharge process, low-capacity batteries may also be over-discharged, which not only reduces battery life, but also may bring the risk of leakage. Therefore, batteries that have been in a state of overcharging and overdischarging for a long period of time are a great safety hazard, and may even cause an explosion or fire. These different capacity batteries may be disassembled from the rechargeable treasure, the core parameters may be inconsistent, and not sure whether the protection plate is added, it is strongly recommended not to use the different parameters of the battery assembly, so as not to cause potential safety hazards.