Wednesday, January 5, 2011
Weak current College】 【rechargeable battery main performance indicators】.
<br> <br> 1. safety performance <br> <br> Safety performance indicators unqualified battery is unacceptable. Most of them are explosive and leak fluid. Explosion and leakage occurs mainly with battery internal pressure, structure and process design (such as .safety valves fail, lithium-ion battery protection circuits, etc.) and should be banned incorrect operation (such as the battery into a fire). <br> <br> 2. capacity <br> <br> Means must discharge conditions, .battery can discharge out of total power. According to IEC standards and national standards, nickel cadmium and nickel hydrogen batteries at 20 ± 5 ° C, to 16 hours after 0.1C charging to 0.2C discharge to the release of 1.0V battery, nominal capacity .of the battery to C; lithium-ion batteries at room temperature, constant current (1C), constant pressure (4.2V) 3 hours under charge to 0.2C discharge after to the release of 2.75V battery, nominal capacity of the battery. Battery .capacity of the unit is mAh and Ah (1Ah = 1000mAh). <br> <br> To AA2300mAh Ni-MH rechargeable battery, for example, indicates that the battery to charge 230mA (0.1C) to 16 hours after 460mA (0.2C .) discharge to 1.0V, the total discharge time is 5 hours, the release of power as 2300mAh. Accordingly, if the current discharge 230mA, its discharge time is about 10 hours. <br> <br> 3. internal resistance <br> .<br> Battery internal resistance refers to the current flow through the battery inside the resistance. Rechargeable batteries of the internal resistance is small, you need a dedicated instrument can measure to more accurate results. General knowledge of the battery is charging State internal resistance, .which means the battery is fully charged when the internal resistance (and corresponding is discharge State internal resistance full discharges the battery, refer to the internal resistance. In General, the discharge State resistance than the charge State of the internal resistance is large, and not .very stable). The larger battery, the battery itself consumed more energy efficiency in the use of the battery. Internal resistance of a large battery charging time heating very ill, so that the battery's temperature has risen dramatically. On the influence of the battery and .the charger. With the increase in the number of times the battery use, because the electrolyte depletion and battery internal chemical activity of lower internal resistance of the battery will have varying degrees of elevation. Lower the quality of the battery the faster the rise. < .br> <br> 4. cycle life <br> <br> Cycle life is the battery can be experienced in the number of times to repeat the charge and discharge. Battery life and capacity into reverse relations, Ni-MH battery cycle life of .up to 500 or more. High-capacity battery life is shorter, but also up to more than 200 times. Cycle life is also closely related to the charge and discharge conditions, generally the larger the charging current (charge faster), the shorter life .cycle. <br> <br> 5. charge retention capacity <br> <br> Charge retention capacity is often speak of self-discharge means in open-circuit condition, battery storage power in certain environmental conditions of retention capacity. Since the discharge .from the battery materials, manufacturing processes, storage conditions, and many other factors. Usually the higher the temperature, the higher the rate of self-discharge. Charging battery, a degree of self-discharge is normal. With Ni-MH battery, for .example, IEC standards provided the battery is fully charged, at a temperature of 20 ± 5 ° C, humidity: 65 ± 20% under the conditions of stay of 28 days, open circuit, 0.2C discharge time shall not be less than 3 hours .(that is, the remaining capacity is greater than 60%). Lithium-ion batteries and battery self-discharge is much smaller. <br> <br> 6. high rate discharge performance <br> <br> That is, high- .current discharge capacity. Digital cameras, electric tools, electric toys, appliances especially high rate discharge performance excellence have batteries. High-current discharge performance main and battery materials and production process. <br> <br> <br> <br> <br .> <br> <br> <br> <br>.