How to distinguish the quality of rechargeable battery? 1. The most useful tool is to directly test and compare these important performance metrics. Since most of the above indicators are measured with dedicated equipment, it is not feasible for the average consumer. There are, of course, indirect ways. For example, if you use the same device (such as a Walkman) and use two different batteries under the same conditions, a more durable battery is naturally a higher capacity product. Figure 2. Weighing, looking at capacity, generally speaking, the same battery technology, large capacity products must be heavier. For example, with the current level of industrial technology, all aspects of performance can reach the standard Aa type 2100mah capacity ni-mh battery weight is generally greater than 29 grams. Figure 3. Look at the appearance of packaging, visual appearance is an important reference means to measure the quality of many products. For the battery, a solid and smooth battery case, clear printing, good packaging material texture is the basis of quality assurance. The qualified battery product shall be printed on the battery packaging mark, manufacturer name, factory address, product type, model number, voltage Mark, implementation standard, warning content, production date, etc. . Dry Batteries also have an expiration date. Most of the poor quality products in the above appearance and packaging indicators will have non-conforming items.Why can’t the battery charge? Recently, the owner reported that the battery in their electric car was out of use, but the electric car had just been bought, and it had been out of use for a month. Throw away the battery can not be recharged, I believe that this day many friends have encountered similar problems, the following series to answer our questions. 1. What’s wrong with not charging the battery? In fact, the above situation is due to the battery for a long time not charging, the panel by irreversible sulfate alkalization attack, resulting in battery problems. The important characteristics of sulfuric acid board are: high voltage during charging, premature gas precipitation, fast temperature rise, fast discharge voltage drop, small capacity. Figure 2. Cause of irreversible sulfation of No. 1 Battery Plate. The storage time is too long, the battery self-discharge rate is high, the battery does not maintain does not charge. Continuous over-discharge or frequent over-discharge or low current deep discharge. The power won’t be back on for another 24 hours. Overcharge or often undercharge. The battery can not be charged at high current. Too high or too low ambient temperature can affect battery performance. For example, the rate of salinization doubles for every 10 degree increase in temperature. Kill. Short electrolyte. Due to the excessive evaporation of water or electrolyte leakage without timely replenishment, resulting in low liquid level, long time exposure to the liquid level on the board, in the board forming sulfate. Figure 3. Batteries should be placed carefully, batteries in a long period of time will not eat enough food, we should pay attention to the battery in daily life maintenance. Electric vehicles placed more than a week, the battery should pay attention to charge and discharge. At the same time to prevent the occurrence of the above-mentioned several situations.