A 100Ah battery can run a fridge for up to 13 hours.
The fridge should only run for a little bit and then shut off for awhile so the fridge should not run all the time.
If you have solar panels recharging the battery when the fridge shuts off then the 100Ah battery should run the fridge forever as long as the sun is shining on the solar panels everyday.
A 100Ah lead-acid deep-cycle battery will run a fridge using 630kWh/year for 13.3 hours.
80% discharge is assumed, but at the recommended DoD of 50% the same 100Ah battery will run the fridge for 8.3 hours.
A lithium iron phosphate 100Ah battery will run the fridge for 15.8 hours at 95% discharge.
To fully and properly charge a 100Ah battery you need to have at least 300 watts of solar.
So you'll need 3 of the 100 watts solar panels or even 2 of the 200 watt solar panels to charge the 100 Ah battery.
The more solar panels you have the better though and if you have more than 100Ah batteries then you need even more solar panels to properly charge the batteries.
100Ah is usually enough for some people who use very little electricity.
Depending on the electricity and amp draw you use you should get 10 hours of use out of the 100Ah battery or if you only use the battery for 5 minutes a day it could last 120 days.
If you have solar panels charging the battery constantly then the battery can last for quite awhile as long as your amp draw is not too much.
You can also wire more than one 100Ah battery together to increase your amp capacity so the battery lasts longer.
To get more amp hours you wire the batteries in parallel and to get more voltage you wire the batteries in series.
When connecting batteries in parallel, the negative terminal of one battery is connected to the negative terminal of the next and so on through the string of batteries.
The same is done with positive terminals, i.e. the positive terminal of one battery to the positive terminal of the next.
A 100Ah battery should run an appliance that requires 200W for up to 6 hours.
A 100Ah battery will run an appliance that requires 3000w for up to 3 hours.
A 200Ah 12 volt deep-cycle lead-acid battery will power a 400W AC fridge for 30 hours, drawing power at a rate of 40 watts per hour.
A 1 hour amp hour battery should last for 100 hours if you draw a constant load of 1 amp.
If you're drawing 5 amps from the battery then the 100 amp hour battery should last 20 hours.
A battery's amp hour rating is based on a consistent load of 5 amps.
What that means is that a 100 amp hour battery that has a constant load of 5 amps on it should last 20 hours.
1 amp hour is 1 hour of electricity flowing for 1 hour.
For example if you have 1 amp hour in your battery then you can draw 1 amp for 1 hour before the battery is depleted.
1 amp hour means that 1 amp of current will flow for 1 hour.
For example if you have 1 amp hour battery the battery will have enough power to flow 1 amp for 1 hour until the battery is dead.
The difference between amps and amp hours is that amps are a unit of electrical current and amp-hours are units of current storage capacity.
An ampere measures electricity.
Volts represent the difference in potential that drives amps to flow through the closed circuit.
Therefore, while amps represent the volume of water, volts carry the water through the circuit.
The meaning of Ah in battery terms is Amp Hours.
The A stands for Amps and the h stands for hours.
So for example if a battery says it has 100 Ah it means the battery has 100 Amp Hours.
An ampere hour or amp hour is a unit of electric charge, having dimensions of electric current multiplied by time, equal to the charge transferred by a steady current of one ampere flowing for one hour, or 3,600 coulombs.
The commonly seen milliampere hour is one-thousandth of an ampere hour.
As the name suggests this means how many amps the battery can deliver in an hour.
For example, a 12V lithium battery with a capacity of 100Ah can deliver 100A to a 12-volt device for one hour.
The same 100Ah battery could supply power for 4 hours (100/25=4) to a 25 ampere device.
One ampere-hour (or amp-hour or Ah) is a current of one ampere flowing for one hour.
The amount of charge transferred in that hour is 3,600 coulombs (ampere-seconds).
A milliampere-hour (mAh or milliamp-hour) is a thousandth of an amp-hour.
An amp-hour is one amp for one hour, or 10 amps for 1/10 of an hour and so forth. It is amps X hours.
If you have something that pulls 20 amps, and you use it for 20 minutes, then the amp-hours used would be 20 (amps) X . 333 (hours), or 6.67 AH.
The key is to use the watts you know to calculate the amps at the battery voltage .
For example, say you want to run a 250 watt 110VAC light bulb from an inverter for 5 hours.
Amp-hours (at 12 volts) = watt-hours / 12 volts = 1470 / 12 = 122.5 amp-hours.
What is the difference between amp-hours and watt hours?
Put simply, the power of an amp-hour (or, thus, mAh) depends on the voltage, whereas a watt-hour is always a watt-hour.
Other variables and terms, such as cycle life and C-rate, also affect the real-world available energy in a battery, but using watt-hours at least eliminates the ambiguity of the amp-hour.