Weak or bad hybrid car battery symptoms

Hybrid cars are cars that use power from both batteries and internal combustion engine to drive the car.

The hybrid batteries are usually high voltage batteries. They have lifespan and they get weak after years of usage.

The symptoms of weak batteries are signs or manifestations that hint us that the hybrid batteries are getting weak or are weak already.

The traction battery (high voltage battery) of a hybrid car is one of the most reliable parts with a reported average life span of ten years.

Some people have used theirs way beyond that. As the car ages, the battery becoming weak is inevitable.


What is a hybrid battery?

When people say hybrid battery, they refer to the high voltage/traction battery.

It is different from the normal 12 volts type found in a conventional car.

In a hybrid vehicle, the 12 volts battery is merely used to power accessories and control units.

The high voltage battery is used to power the electric motors which drives the wheels.


What causes the hybrid battery to become weak?

1. Normal ageing of the battery can make it to become weak meaning that it served during its useful life.

2. Putting transmission in neutral at stops. This might not apply to every hybrid car that has been produced. Whenever the transmission is in neutral, the battery does not charge. This is the way it is designed to operate. This is one area where driving a hybrid is different from driving a conventional internal combustion unit cars.

3. Battery pack cooling problems can affect the cells. There is a fan unit attached to the battery pack that cools it. When this fan goes bad, the chances of the battery being affected is high.

4. Charging system problems can cause the battery to either undercharge or overcharge. Parts of the charging system that can go bad are inverter/converter and battery control unit or even the generator that also acts as moror.5. Battery sitting for long without use. This can happen if the car is parked for many months without removal of the battery fuse. The battery is going to discharge gradually until it finally becomes weak.


How do we know that the hybrid battery is weak?

1. Poor gas mileage.

Weak batteries draw high currents from their charging sources. Since the engine is responsible for changing the battery, there is a high load that is placed on the engine during charging. This in turn causes high fuel consumption as the engine needs fuel to carry the extra load placed on it.

2. Erratic battery charge state.This can be seen in the battery indicator on the dash. Now it is full and suddenly it goes to a drained state again. This is a sure call for battery replacement.