how to tell if a battery is dead

1.How to tell: the sign of dead battery

When a battery nears its final stage, it will show many symptoms. These symptoms are almost common irrespective of the battery you are using. If you are clever enough to Hard carbonunderstand the signals, you can easily make backups or standby arrangements before reaching a dead-end situation.

If you want to check whether your battery is dead, there are some easy things you can check and confirm the status of the battery.A dead battery won't give any types of response when you try to start the car.

Signs of a dead battery

From a practical point of view, when you try to start the car,

  • If the car gives a slow dragging start, you can assume that the battery's condition is terrible.  
  • If your car battery is weak, sometimes the engine will start, and suddenly it will stop. It is a clear indication that your car battery is dead.  
  • If there are no headlights and horns, it is a symptom to check your battery.
  • Sometimes, you can see the battery has enough power to burn the headlight and horn, but when you crank the engine, the headlight becomes dim, and your car won't start. It happens because there is not enough power left in the battery to crank the engine.  
  • If your battery is more than 4-6 years old, it is also time for you to change the battery.  Sometimes your car panel light will flash because of severe engine trouble or battery issues.

These are the common tips on how you can identify if your car battery is dead.

2.How to test a dead battery

There are different methods to check if the battery is dead or in a poor state.  These methods will vary depending on the battery since there are many types of batteries.  For alkaline batteries, you can do a drop test.  For other batteries, you can use a multimeter voltage tester or voltmeter.  Smartphone users can check the battery condition by doing an app-based diagnostic test or a voltage test.

How to check if your lithium 18650 battery is dead

2.1 How do you check if a battery is bad?

If the battery is in a swollen stage, then it indicates the battery's bad stage. If you can feel a foul smell from the battery, it will also demonstrate its poor condition.  

  • Drop testing for alkaline batteries

It is a simple test, and anybody can do it without technical expertise.  Hold the battery vertically with the flat side (negative side) facing the tabletop's surface.  Just drop the battery from 10-15cm to the surface.  If it bounces, then it is an indication of its lousy stage.  The battery may not be dead, but it is a warning about the state of the battery's condition.  If it does not bounce, then the battery is good.

  • Voltameter test

Acid, Alkaline, and lithium batteries can check with a voltameter to determine the stage of the battery.  Check the positive and negative marking of the battery and connect with the respective probs of the voltameter.  Since all batteries are DC, select the voltameter setting to DC before checking the battery.  If the battery voltage shows less than the discharge cut off voltage, it is an indication that the battery is dead.

  • Load testing using multimeters

Load test using multimeters is the best way to understand the voltage condition of a battery.  Depending on the battery’s voltage marking, you must select the correct load setting.  Do testing by connecting with the positive and negative probs of the multimeter with the battery terminal, respectively, and get the mAh reading.  If the mAh reading is below the required level, it indicates its bad stage. You cannot do this test with lithium batteries because multimeters do not have the features to test their load capacity.

Load testing using multimeters
  • Battery tester

Using a battery tester is more convenient than a multimeter, voltameter, or drop test.  It can give the correct status of the battery condition.  You must place the batteries in the designated slots and check the display reading.

2.2 How can I test my battery at home?

There are many methods to test the car battery at home.  The simple and easy way to check the car power condition of a battery at home is to do a load test.

  Load Test: Check the following steps.

  • Turn on the headlights without starting the engine.
  • Keep it in on position for about 15 minutes.
  • After 15 minutes, try to start the engine.
  • If the brightness of the battery slows down, then it is a warning sign, and you must go for a replacement.

Corrosion: Another home checking method is to check the corrosion on the terminals.  The corrosion accumulation happens because of the hydrogen gas release, and the corrosion at the battery terminals will hinder the power supply from starting the engine.  Keep your car terminal clean for better battery life.If you want to deal with this problem, you can find the methods in how to clean battery corrosion article.

Noise: The third method is by checking the noise you are getting after putting the key in the ignition socket.  If you hear click-click noise instead of a roaring sound, it is an indication that your battery is in bad shape.

App test: Yet another useful method of checking the battery level at home is to go for virtual testing.  There are many apps available for this purpose.  You have to enter your car's details; the app will let you know the battery condition, which will be a helpful option.

Is it possible to test the battery at home

Lithium or alkaline batteries checking:

For checking lithium or alkaline batteries, you can use a multimeter or voltameter or even a battery checker to evaluate the battery condition at home.Or you can console the Professional battery shop staff if you don't have any of this testing equipment.

2.3 How can I test a car battery without a tester?

Load testing is the best way to test a battery if you don't have a battery tester.

3.How to charge:revive the dead battery

3.1 Can you revive a dead battery?

Yes, you can.  There are some easy methods to revive a dead battery.

Revival of a dead battery

3.2 What do you do when your car battery is completely dead?

A dead car battery can revive using a jump start.  Using the jump start cable, you can give a temporary connection to the car that needs power.  First, connect the positive terminal of the good battery to the positive terminal of the bad battery.  Before you make the connection, remove the ignition key of both cars and make the cable connections.

Then take the connection from the negative terminal and connect with any solid metal part of the car that requires power, preferably a strut tower or somewhere it looks safe.  Then start the car with a good battery and allow it to run for two minutes.  After two minutes, start the engine you want to charge.  Once the engine starts running, drive it for some time so that it can get recharged.  A jump start is an easy way to revive a dead car battery.

3.3 Reviving a lithium-ion battery

If you want to revive a lithium-ion battery, some lithium-ion batteries will be equipped with smart battery management systems. For protection purposes, the battery management system will automatically cut off the circuit of the battery when the battery voltage is lower than the discharge cut off voltage, that is, overdischarge. At this point, you just need to restart the smart BMS and recharge again.

3.4 How long should it take to charge a dead car battery?

If you need to recharge your battery with about 4-8 amp fully, the battery is required to charge for about 10-24 hours.

Time required to charge a dead car battery

4.How to remove:How can I get my car out of dead battery?

How can I get my car out of dead battery?

It is easy to remove a dead battery from your car.  First, you may remove the switch from the ignition socket.  Then using a spanner, remove the negative terminal first, followed by the positive terminal.  Then remove the battery bracket and take out the battery.  While refixing a new battery, connect the positive terminal first, followed by the negative terminal.