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An average car battery has a capacity of around 48 amp hours which means that, fully charged, it delivers 1 amp for 48 hours, 2 amps for 24 hours, 8 amps for 6 hours and so on.

## What should a battery charger read when fully charged?

When Fully Charged, How Many Volts Should A Car Battery Have? Fully charged automotive batteries should measure at **12.6 volts or above**. When the engine is running, this measurement should be 13.7 to 14.7 volts.

## How many amps should a car battery draw when off?

Most vehicles draw some battery current when the key is off, thanks to the clock and the internal memory of engine computers, body-control modules, and radio presets. Altogether, they draw a very small amount of current. **Fifty milliamps** would be a safe upper limit for this, though many vehicles will draw less.

## How many amps are in a 12 volt car battery?

Car batteries will typically have a capacity of **48 amp hours**. What this means is a fully-charged 12-volt car battery rated at 48 amp hours can deliver 1 amp for 48 hours or 2 amps for 24 hours.

## Can you overcharge a 12-volt battery?

A 12V lead-acid **battery won’t be damaged by overcharging if the voltage is kept low** and the charging current is less than the Ah capacity. The battery may become overheated if it can put out more current than it can take. …

## Is 11.9 volts enough to start a car?

The normal voltage needed to start the car begins from 12.6 volts. At the time of exploitation, this parameter is between **13.7 to 14.7 volts**.

## Should I charge my battery at 2 or 10 amps?

It is **best to slow charge the battery**. Slow charging rates vary depending on the battery’s type and capacity. However, when charging an automotive battery, 10 amps or less is considered a slow charge, while 20 amps or above is generally considered a fast charge.

## How long does it take to charge a car battery at 2 amps?

How Long To Charge A Car Battery At 2 Amps? It will take a lot of time to charge a car battery using a 2amp charger. The average time to charge a 48amp battery fully, using such a charger is **24 hours**.

## Is 300 amps enough to start a car?

How many amps do I need to jump start my car? **400 to 600 amps** will be more than enough to jump-start any normal, consumer vehicle. Commercial vehicles may require up to 1500 or 2000 amps. Compact and small vehicles can be boosted with as little as 150 amps.

## How long will a car battery last with a 5 amp draw?

Batteries are rated for 5 amps **over 20 hours** of time

What that means is that a 100 amp hour battery that has a constant load of 5 amps on it should last 20 hours.