A dead battery can cause you to get stuck in dangerous places if not replaced immediately. The alternator and battery work together to power the vehicle's entire electrical accessory.
The battery also conducts some power to the stator and rotates most of the engine components. There are several symptoms that may indicate that the car battery is dead. The most obvious thing is that the starter only clicks when you try to launch it, but there are a few others that you should know:

1.
Slow crank

If you notice that your engine takes some time to start / get sluggish, you may notice that your battery may be dead. A good battery should last for about 5 years.

When the battery is exhausted, the car may crank slowly and it is tedious. You must rule out the possibility that your starter could be the problem or spark plugs worn out. To avoid a plug problem, you will notice that the starter cranks at normal speed. The problem could also be a parasitic outflow that you must identify.

2.
Dim Headlights

If you notice your headlights are dimming even when the accelerator pedal is full, your battery is in the deathbed. Headlamps need a fully charged battery to shine well in the dark. It is dangerous to drive with such lights as you can not foresee and arriving cars can not recognize you (especially on foggy roads). This is especially noticeable when the alternator is worn out.
In addition, problems with the car stereo or the air conditioner may occur when the battery is exhausted.

3.
Check the engine light

There are countless reasons why a light goes on, a dead battery is one of them. If your engine light comes on, you must use a voltmeter to check the battery voltage.

4.
Click Sound

The starter needs the battery power to drive the motor. When the power is low, the starter will not get enough power to start the engine, and you will hear a click sound under the hood.
A dead battery will not produce a sound when you turn on the ignition. But there are also other causes and you have to rule out faulty ignition switches, starters and the fuse.

5.
Misfire

Closely related to a slow crankshaft is the misfire of the car. The battery can occasionally cause sparks in the combustion chamber, which can cause the fuel-air mixture not to ignite properly. As a result, more fuel accumulates in the combustion chambers, which is then conducted along the exhaust gas chambers.
However, before you replace the battery due to misfires, make sure you have eliminated other related problems.

6.
Lack of dome light

When the battery is low, you will see a faint door light, but when it is empty, the door lights will not go on. If you replace the battery and the problem persists, the problem may be with the door wiring.

7.
Malfunctioning Alternator

The battery powers the vehicle's electrical appliances in conjunction with the alternator. As the car moves, the alternator charges the battery. Over time, the alternator begins to develop loose straps and finally stops working. In this case, the battery will not fully charge and you will see signs of an empty battery.

8.
Battery corrosion

In times of extreme weather, lead sulphate forms at the battery poles, which leads to corrosion. This accumulation of lead can affect the smooth operation of your battery. To remove the corrosion, a simple solution of soda or coke can be used. It is recommended to change the battery every 4 to 5 years.

LAST WORDS

If the car does not start, the battery may be low. You must first examine the door lights and headlights and see if they are working or weak. Loose wiring can be the cause. Therefore, it is of utmost importance that you exclude other causes for not starting the vehicle. If you turn the ignition key and nothing happens, there may be a dead battery.
Source:
http://www.eliancars.com/2019/12/major-reasons-why-your-car-battery.html#more
[img]https://1.bp..com/-j3vNCSdqMCI/XeWcdO_cwgI/AAAAAAAADU4/7r_JECjzkPQBdpCWCZmui4eFP4QhRuRtACLcBGAsYHQ/s320/flat.jpg[/img]


cc : Lalasticlala, Marpol

Nice information bro, but pls what then could have gone wrong with mine? It works fine on a good day but if the car is left like 3 days without use by the 4th day it would have gone flat and would need some to help recharge a little.