Two Test Methods for battery

The detection of zinc-manganese dry is quite common, there are generally two methods. The first method is to measure the instantaneous short-circuit the battery internal resistance to estimate the battery and determine the relevance of the battery; second method involves using a current meter in series resistance of the appropriate strength by measuring the discharge current of the battery to the load resistance of the battery to determine the relevance of the battery. Dell Inspiron 1525 Screen Dell Inspiron 1526 Screen

The first method is the biggest advantage is simple and high current with a multimeter can file directly to determine dry cell battery, a big disadvantage test today, far beyond the limit of battery discharge current allows, to some extent affect the battery use life. The second method has the advantage of the current test, security is good in general does not affect the battery life, the rebate is a bit more complicated.

I use the meter on one of MF47 2 old batteries and battery, 2 were tested using the two methods compared. Suppose that ro is the resistance of the internal battery, RO is the resistance ammeter, with a test on the other hand, RF is the series resistance further, the resistance of 3Ω, power of 2W. Dell Inspiron 1545 Screen Dell Inspiron 17 Screen

The measured results are as follows. New 2 batteries E = 1.58V (measured with a profile of DC voltage 2.5V), 50kΩ resistance voltmeter is much larger than ro, they may be similar to that 1.58V is the battery of electromotive force, or voltage open circuit. Using the first method, the meter serial 5A DC current file indicator, internal resistance RO = 0.06Ω, the measured current is 3.3A. Then ro + RO = 1.58V ÷ ≈ 0.48Ω 3.3A, ro = 0.48 to 0.06 = 0.42Ω. Using the second method, the current measure of 0.395A, RF + RO + RO = 1.58V ÷ 0.395A = 4Ω, the current resistance of 0.6Ω 500mA stall then ro = 0.4Ω = 4-3-0.6. Dell Studio 14 battery Dell Studio 15 battery

Former two batteries when you use the first measured, first measured the open circuit voltage E = 1.2 V, an indicator of resistance RO = 6Ω, a reading of 6.5mA, 50mA DC current meter set of files RO + RO = 1.2 V ÷ ≈ 184.6Ω 0.0065A, ro = 184.6-6 = 178.6Ω. Using the second method, the measured current of 6.3mA, RO + RO + RF = ÷ = 1.2V 0.0063A 190.5Ω, ro = = 190.5-6-3 181.5Ω.

Obviously the results of both methods are consistent. The final results of the small difference is due to reading error, the error resistance RF and the contact resistance caused by other factors, this small error will not affect the judgments on the battery. If the measured battery capacity is small, high voltage (eg 15V, 9V battery laminate), the resistance should be increased to meet the RF. dell latitude d820 battery dell latitude d830 battery