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

Contents

Battery capacity decreases as the rate of discharge increases. Batteries (say 100ah battery) have been tested at a given discharge rate of 20 hours. That means a constant use of 5 amps an hour for 20 hours (5 x 20 =100).

## How long will a battery last with a 1 Amp draw?

It depends on the power demand of your system. 3 Ah means that if you pull 3 Amperes from the battery for 1 hour, it will be discharged completely after 1 hour. So if you pull 1 Amps, it will last 3 hours.

## How do you calculate how long a battery will last?

To determine how long your battery will last, calculate the battery’s total capacity and divide it by your circuit’s power. Multiply the battery’s reserve capacity by 60. With a reserve capacity, for instance, of 120: 120 x 60 = 7,200.

## 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 amp hours does it take to start a car?

On average a 4 or 6 cylinder car will draw about 250 amps for 3 seconds to start. That works out to be 0.21 Amp-Hrs. The alternator on a car can easily restore that amount of energy in 30 seconds at about 40% efficiency. Which means about 0.52 Amp-Hrs are needed from the alternator to recover the battery.

## How long will a 100Ah battery run an appliance that requires 1000w?

Table: Running times for various AC loads

100Ah deep-cycle lead-acid battery with AC loads with inverter – 50% recommended discharge
800 0.65
900 0.57
1000 0.52

## How long will a 100Ah battery run an appliance that requires 100W?

A 12V 100ah battery can run a 100W appliance for 20 hours at a draw of 5 amps/hour. Due to inverter inefficiency and energy losses, drawing more than 5 amps an hour reduces the ah capacity rapidly, but drawing less slows the discharge rate.

## How long will a 100 Ah battery last?

A 100 ah battery should give you (100/10=10) 10 hours of usage. If you use it for 5 mins a day, it could last 120 days.

## How long will a 200Ah battery last?

Depending on how many amps your appliances are drawing, a 200Ah battery will likely last you between two and eight hours. At 25 amps, you can expect the 200Ah battery to last eight hours.

## How long does a 4.0 Ah battery last?

So by that logic, a 4.0Ah battery should last for 2 hours in the same electric mower.

## How much should car battery voltage drop overnight?

Shouldn’t go much below ~12.6v and can go up to 13 to 14+volt while running/charging. Any decent car battery will only lose at most 0.01V maximum, the security of the car will draw some current but it should only be low.

IT IS INTERESTING:  Quick Answer: Do electric cars wear tires quicker?