How to test the battery level?

How to test the battery power Generally, it is satisfactory to test the power of the zinc-manganese dry battery. There are generally two methods. The first method is to estimate the internal resistance of the battery by measuring the instantaneous short-circuit current of the battery, so as to determine whether the power of the battery is sufficient. The second method is to use the resistance of the a-series ammeter to calculate the resistance of the battery by measuring the discharge current of the battery, and then determine whether the power of the battery meets the requirements. The biggest advantage of the first method is simplicity. A multimeter with a large current range can directly identify the power of the dry battery. The disadvantage is that the current inspection is very large, which far exceeds the limit of the discharge current of the dry battery, which affects the service life of the dry battery to a certain extent. . The advantage of the second method is that the inspection current is small and the safety is good. Generally, it will not have a bad influence on the dry life of the battery. The disadvantage is that it is more troublesome. The MF47 multimeter was used to detect the difference between the new type of electric energy meter and the ordinary electric energy meter. 2 dry batteries and an old no. 2 Dry batteries. Assuming the internal resistance of the ro dry battery, the ro amperemeter resistance, and the second test method, the radio frequency is an additional series resistance, the resistance 3,2w. The measurement results are as follows. The new 2Eu003d1.58V battery (2.5V DC voltage profile measurement), the internal resistance of the voltmeter is 50k, which is greater than ro, which can be approximated as 1.58V battery electromotive force, or open circuit voltage. Using the first method, 5 multimeter DC current gear and the internal resistance of the meter ROu003d0.06, the measurement current is 3.3A. So ro+rou003d1.58V3.3-0.48 material, rou003d0.48--0.06u003d0.42. Using the second method, measuring current 0.395A, RF +ro+rou003du003d40.3951.58V, current 500mA, internal resistance 0.6, so rou003d4-3-0.6u003d0.4. Old 2 cells are measured using the first method, measuring open circuit voltage Eu003d1.2V, meter internal resistance ROu003d6, reading 6.5mA, multimeter 50mA DC transmission, RO+ROu003d1.2V0.0065 to material 184.6, RO6u003d184.6u003d 178.6. Using the second method, measuring current 6.3mA, ro+ro+RFu003d1.2Vu003d0.0063-190.5, ρu003d190.5-3u003d181.5. The results of both inspection methods are significant. After all, subtle differences in accounting effects are caused by factors such as reading errors, RF, and contact resistance. For example, subtle errors will not affect the identification of battery capacity. If the capacity of the battery to be tested is small and the voltage is high (such as 15V, 9V laminated batteries), an RF resistor should be added. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: How should citizens buy electric vehicle batteries?