How to Check Car Battery Performance
The estimated life of car batteries is three to five years. However, batteries require regular maintenance and charging to work adequately for that estimated lifespan. Many factors can damage the battery and reduce its efficiency and lifespan. Regular checks ensure that you are getting the most out of the battery, and there is no damage or drain. In this guide, we have mentioned different ways to test a car battery’s performance and health.
What Is the Optimum Battery Performance?
The average car battery voltage is 12.6 v. This average increases to 13.7 v to 14.7 v when an engine is running. It is the optimum level of voltage that automotive batteries should supply to cars. This average can vary as per the size of the battery used in your vehicle.
Tests to Check Car Battery Performance
With regular checks and maintenance, you can avoid dealing with a dead car battery before it’s time for a replacement. These tests can predict the health and remaining life of the battery so that you know when it is time to change the battery and also identify any issue that’s affecting the battery’s health.
See the following guide on how to test a car battery to see if it is working as efficiently as it should.
Voltmeter
You can check if the battery is drained or not with the help of a voltmeter. Follow the process mentioned below.
- Switch off the ignition and remove the key.
- Put a positive voltmeter lead on the positive battery terminal.
- Put a negative voltmeter lead on the negative battery terminal.
- Reading on the voltmeter should be 12.4v to 12.7v. If it is greater or lesser than this, it reflects inefficient battery performance.

Engine Crank
The engine crank can also explain the battery’s health. But you will need an assistant and electronic devices like; voltmeter, ammeter, power probe or multimeter. These devices are essential for checking batteries, if you do not have any of them, buy auto accessories for sale in the UAE.
- Connect the negative lead to the negative terminal of the battery.
- In a similar manner, connect the positive lead to the positive terminal.
- Switch on the ignition and observe the voltage on the device.
- If voltage is less than 9.6, it reflects the deteriorating performance of a battery.
Power Probe
A Power probe is a tool used to measure the performance of electric circuits. The device is more accurate and simple to use.
- Attach the Power probe’s positive lead (clip) to the positive terminal of the battery.
- Similarly, attach the negative lead (clip) to the negative terminal.
- Connect the tip of the Power probe located in the center to the positive terminal.
- Check the voltage reading as per the optimum level.
Hydrometer
Hydrometers are used to check battery performance by measuring the Specific Gravity (SG) of electrolytes. This process only works when the temperature of the electrolyte is 26℃. Therefore, before obtaining car battery test results ensure that the battery is at a suitable temperature.

- Remove caps of battery cells.
- Insert hydrometer in each cell.
- Squeeze the rubber bulb and let liquid fill in the tube.
- Note reading (g/㎤) and match each cell reading with the optimum levels.
- The cell is working 100% to 75% if the reading is between 1.274 to 1.239.
- The cell is working 74% to 25% if the reading is between 1.238 to 1.201.
- The cell is dead if the reading is below 1.200.
Battery Analyzer
The battery analyzer is an electronic device that is specifically used to test a car battery’s performance. This device can detect the battery’s voltage, the efficiency of the alternator and starter.
- Put the negative lead on the negative terminal of the battery.
- Now, place the positive lead on the positive terminal of the battery.
- Press the ‘Enter’ button and observe the reading.
Safety Precautions for Battery Testing
You can test a car battery’s performance at home, but it is a riskier task. It is necessary to take safety precautions while checking battery performance at home.
- Wear protective glasses, gloves and apron while working with batteries.
- Never work on the battery when the ignition is on.
If you are planning to buy a used car for sale in the UAE, you can check battery performance to see if it needs a replacement.
Stay tuned to UAE’s leading auto blog for more information on car care and maintenance.