.Meet the relevant national standards and requirements for batteries .All finished battery products are calibrated and tested before delivery. They can be used directly and normally.This is a combination battery that can be used in consumer electronics, home appliances, and toys. It can be recharged. The 18650 battery core is used. The advantages of rechargeable batteries are economy, environmental protection, sufficient power, suitable for high-power, long-term electrical appliances (such as walkmans, electric toys, etc.). The voltage of rechargeable batteries is lower than that of disposable batteries of the same model. AA batteries (No. 5 rechargeable) are 1.2 volts, and 9V rechargeable batteries are actually 8.4 volts. Now the general charging times can be about 1000 times. As of February 2012, there are only five types: nickel cadmium, nickel hydrogen, lithium ion, lead storage, and iron lithium. Memory effect: The new battery has fine crystal grains of the electrode material and can obtain the largest electrode surface area. The battery content is crystallized due to use. After the crystallization is formed, the crystal grains increase, also known as (passivation), which reduces the available electrode area, and the grown crystal grains will increase the self-discharge and make the battery The capacity is reduced and the performance is impaired. This is the memory effect. The memory effect occurs because the battery is partially charged and discharged repeatedly incompletely. 