Theoretically, the smaller the charging current is, the better the battery will be. If the charging time is too long, it is certainly not user-friendly for users. Therefore, the general standard is 0.1-0.2c when charging. Here, C is the rated capacity of the battery Take a battery with a capacity of 10000 MAH as an example. The charging current is 2000 ma. Theoretically, it can be fully charged in five hours. The capacity MAH = current ma * time h. but in fact, it is to protect the battery Battery charging can also be divided into three stages: constant current charging, constant voltage charging and silk current charging Therefore, the actual charging time should be longer than 5 hours or slightly longer than 6 hours. The calculation method of battery charging time: divide the battery capacity by the charging current and multiply by the coefficient 1.2-1.1. The unit of time is hour
Maybe you don't understand why you should use the three stages of constant current charging, constant voltage charging and silk current charging to charge the battery. Isn't it a waste of time? Let's introduce these three charging stages, and you will understand the mystery
Constant current charging is a charging stage in which the charging current remains unchanged and the charging voltage rises approximately linearly. If the current of 0.1-0.2c is directly used for charging, even if there are no other accidents, the battery life will be shortened due to excessive charging heating, etc. Therefore, this is why constant current charging starts with the charging current remaining unchanged and the charging voltage rising approximately linearly. In fact, it is for the purpose of prolonging and protecting the service life of the battery
Constant voltage charging has different charging voltages according to different voltage levels. Therefore, you can't choose the charger only according to the current For example, a battery charger charges a 5V battery and cannot charge a 12V or 6V battery
Silk current charging is also different according to different batteries. It is generally called floating charging current Its size is closely related to the battery capacity. For example, the normal charging current < constant current charging current > of a 10000mah battery as an example may not be as large as the floating charging current of a large capacity battery. Excessive constant current charging current is most likely to cause battery overcharge, which will affect the service life of the battery and even destroy the battery Because the most basic protection of battery is two: don't overcharge and don't consume too much electric energy If you violate these two rules, the capacity of the battery may be reduced if it is not damaged immediately
But generally speaking, for example, lithium batteries are equipped with charge and discharge protection circuits After knowing this, you may understand why battery charging needs three stages: constant current charging, constant voltage charging and silk current charging
Generally, the charging time of the battery of digital electronic products is designed as 6 hours. This purpose is to ensure that users can fully charge the battery during the sleeping time. In particular, digital products with frequent charging, such as mobile phones and tablet computers, can enable users to plug in the electronic products before going to bed at night and fully charge the battery before waking up in the morning This is also a more humane consideration Therefore, in consideration of the longest service life of the battery and the convenience for users, designers will try to minimize the charging current of the battery charger
The power adapter manufacturer asks xinjukang: http://www.xjkpower.com
QR code