Battery capacity tester circuit

Two voltage dividers circuit are used to monitor the voltages across the load resistance. My tester puts AA batteries through a discharge test and reports the capacity in milliamp-hours ( mAh ) so you can compare battery capacity. The discharging circuit is relatively simple, each battery has a corresponding load resistor that discharges the battery when the FET is switched ON.

The circuit uses an electromechanical clock and a DVM (digital voltmeter). This is mainly due to the .

Find this and other hardware projects on Hackster. To automate the testing of (camera) batteries and to make the tests repeatable I came up with a small circuit controlled by a Arduino microcontroller - you can see . Li-ion batteries have integrated circuit to protect a cell that cuts off circuit to prevent from over discharging. Of course, this means you need a reliable battery tester , but it also means you can limit the damage to the cost of a battery or two and a one-time investment of time and money in building a suitable tester.

Many commercial battery testers consist of nothing more than a resistor, . Integral accurate battery capacity test using transient recorder and simple test circuit. Assessing full charge is the easy part.

Method (a) A fully charged Lithium Ion single cell battery will have an open circuit voltage of about 4. Some cameras use two cells - double the expected voltages. Laptops and other larger devices use or more cells. The Arduino based capacity tester of true battery power is capable of measuring almost any type of rechargeable or non-rechargeable batteries by fully discharging the battery with known current and log data to PC. Battery Capacity detailed review. A full lab testing of batteries can be obtained by connecting the discharge circuit to Arduino.

Add a temperature sensor to track ambient temperature during the test since that certainly affects battery capacity. The only truly accurate way to measure the current capacity of a battery is by connecting the battery to a constant current load and measure how long the battery can sustain that current before its voltage drops below a recommended “ cutoff” point. Home made battery capacity tester for primary and rechargeable cells. I have found the life of fully. I suspected my fairly new rechargeable batteries are either self-discharging at an alarming rate, or the capacity varies.

I decided to design a tester. I designed the circuit to draw 250mA from the battery. Even this smaller AAA battery weighs grams. The batteries actually arrived in a charged state, and I read about 1.

Then I set the meter to current, and .