Before answering this question, we are going to give some brief technical notes:

Every battery has two main characteristics: Voltage (V) and Capacity (Ah).

Voltage of a battery (V)

The voltage of a battery is the difference in potential or voltage that exists between its poles.

If we consider Ohm's Law: Voltage = Intensity * Resistance we have:

Resistance: It is the resistance offered by what we connect to the battery. If we connected a direct cable from one terminal to another, the battery would give its maximum current intensity. For this reason, it is very dangerous to connect any current conducting element between the two battery terminals. Be careful, therefore, with connecting a direct cable, putting something metallic between the two terminals, or even spilling water on the battery.
Intensity: It is the force that the battery can provide at all times.
Voltage: As the resistance of what we have connected to the battery is fixed, the higher voltage we have, the more current we can provide. Or put another way, the voltage will determine the current intensity and the higher the voltage, the more intensity we will give.
Some conclusions can be drawn from all this:

- If a battery is discharged, it will give less intensity of current.

- If we increase the voltage, the current intensity will automatically increase.

In a car, everything that is connected to the battery is prepared to operate at a voltage of 12V. What would happen, therefore, if we could connect a 24V battery or 2 12V batteries in series? After all that has been seen, the answer is simple: if we double the voltage, the current intensity would also increase twice and we would run the risk of burning or damaging everything that is connected to the battery.

Likewise, if the battery were to discharge, the current intensity would decrease and the engine would not be able to start, some circuits would not receive enough energy to function correctly, etc ...

Important: Never connect a higher voltage battery to the vehicle

Capacity of a battery (Ah)

On the other hand, the capacity of a battery, which is measured in Ah, represents the amount of electricity that a battery can provide. The more capacity (Ah) a battery has, the more electricity it can provide.

In theory, a battery that has 100Ah could give a current intensity of 100 Amps for 1 hour, an intensity of 1 Ampere for 100 hours, or 2 Amps for 50 hours. However, this is not always the case, as the faster a battery discharges, the more power it loses. Therefore, it is common to find batteries that have the following capacity:

Varta LA95 Battery Capacities
Ah 20hr 95Ah
Ah 10hr 90Ah
Ah 5hr 85Ah

That is, the same battery could give 4.75A for 20 hours (4.75A x 20 hours = 95Ah c20), 9A for 10 hours (90Ah c10) or 17A for 5 hours. If we did not have the power losses, the battery should have been able to provide 19A for 5 hours (95Ah) or 9.5A for 10 hours (95Ah).

Summarizing:

  • The capacity of a battery is the energy that the battery can provide.
  • The more capacity a battery has, the more energy we can get from it.
  • The faster we discharge a battery, the less energy we can obtain from it.

Therefore, answering the initial question, if we replace a car battery with a higher capacity one, we will be able to leave the elements that depend on the battery in operation for a longer time. In addition, with the same consumption the higher capacity battery will discharge less, which in the long run will result in a longer battery life.

Is there a problem if we install a higher capacity battery?

Although this is not always the case, because the battery design can be different, a battery with a higher capacity will also have a higher CCA, which could be said to be the maximum intensity it can provide in an instant. That does not mean that he is able to provide it in all situations, only when the team needs it.

And this is where we can find the problem: if the equipment is faulty, has a ground problem or a short (connection of positive and negative), the battery with greater capacity will provide more intensity than a normal one and could damage part of the electronics ( although electronic systems are usually protected by fuses, precisely to avoid these situations).

But this effect will only be very apparent if the difference in CCA is considerable. For example, taking it to an extreme, the problem could occur if we try to start a motorcycle with a truck battery and we have some kind of ground or connection problem.

Under normal circumstances, there should be no problem installing a larger capacity battery. On the one hand, there is usually not enough space to install a battery with a large starting difference (CCA) and, on the other, by starting with a greater capacity (Ah) and starting force (CCA), we will increase the battery's durability. , since both parameters degrade over time.

In short, if we install a higher capacity battery, we will increase battery life, improve starting and, in addition, we will be able to use the electronic equipment of our vehicle for a longer time.

However, what happens if we don't have a space to install a larger battery?

For these cases, manufacturers usually manufacture batteries of different benefits for the same size. The most basic range usually has less ah and the highest range contains the highest performance, both in amp hours and starting capacity.

For example, Varta for the same size has a battery of 70Ah, another of 74Ah and another of 77Ah. The lowest range is the 70Ah and the highest range is the 77Ah. In these cases, the manufacturer always recommends installing the highest-end (77Ah), especially if the car has a large number of electronic components.

Battery Varta E13 12V 70Ah: Size: 278x175x190 Battery Varta E11 12V 74Ah: Size: 278x175x190 Battery Varta E44 12V 77Ah: Size: 278x175x190


In short, whenever you have the opportunity to choose, install a battery with the highest possible capacity