**A 12v 100ah lithium battery with a 100% DoD limit will last between 22 hours (running a 50-watt AC appliance) to 36 minutes (running a 2000-watt AC appliance).**

In this post, you’ll learn how long will a 100ah battery last running a different size AC or DC load (with examples).

**Need an easy solution?** use our battery runtime calculator ( given below ) and ” Enter the battery specs and the total load in watts ” to find out how long will a 100ah battery last

Also, I’ll share the manual calculation method and some other important points to keep in mind that the other websites aren’t talking about.

## How Long Will 100ah Battery Last – Calculator

**Note: **use my solar panel size calculator for a battery to recharge your battery in desired hours with solar panels.

### Assumptions

**Inverter Efficiency:**90%**Lead-acid battery:**50% depth of discharge limit**Lithium (LiFePO4):**100% depth of discharge limit

**Battery Depth of discharge DoD:** is the percentage of the battery that has been discharged relative to the total battery capacity. The recommended depth of discharge limit for lead-acid, AGM, and gel batteries is about 50%. Only lithium (LiFePO4) batteries can be fully discharged to 100%.

### How To Use The Calculator

**Enter the battery capacity in amp-hours (Ah):**in this case, it’ll be 100**Enter the battery voltage:**is this a 12, 24, or 48-volt battery?**Select the battery type:**Select “Lead-acid” if you’re using a flooded or sealed (AGM or gel) lead acid battery. Select “Lithium (LiFePO4)” if you use a lithium-iron phosphate battery.**load Connected with inverter?:**Are you using an inverter to run the load or is the load connected directly through the battery?**Enter total load in watts:**Enter the total load in watts (e.g 500 for 500 watts of output load)

After entering the information, click** “Calculate” **button to find out how long will a 100ah battery last

if you’ve got some time keep reading… I’ll share a manual calculation method that you can use in the future to calculate any size battery runtime on any load and also some additional information about batteries that will affect the battery last time.

### Example 1: How Long Will A 100ah Battery Run An Appliance That Requires 1000 Watt

12v 100ah battery will last anywhere from **32 minutes** (with lead-acid battery) to **60 minutes** (with lithium battery) while running an appliance that requires 1000 watts

### Example 2: How Long Will A 100ah Battery Run An Appliance That Requires 400 Watt

12v 100ah battery will last anywhere from **1 hour and 22 minutes** (with lead-acid battery) to **2 hours and 42 minutes** (with lithium battery) while running an appliance that requires 400 watts

## Video – All About Battery Basics (Must Watch!)

This guys has explained in detail the battery basics, MUST watch to understand how batteries work (charge and discharged)

## Steps To Calculate 100ah Battery Runtime

Follow these steps to calculate the battery life/runtime while running a load.

### Steps

**1- Converter battery ah into watt-hours (Wh)**. to calculate the battery capacity in watt-hours use this formula

**Battery capacity in watt-hours **= Battery amp-hours (Ah) * Battery Volts

let’s say you have a 12v 100ah battery

`100ah battery in watts = 100 * 12 = 1200 watt-hours `

**2- Multiply the battery watt-hours to the battery depth of discharge limit**. **( Default battery depth of discharge limit, Lead-acid battery: 50% DoD limit; Lithium: 100% DoD limit )**. Let’s say you have a lead-acid type battery

`Battery capacity in wh after DoD limit = 1200 * 50% = 600wh`

**3- Multiply the battery capacity after the DoD limit with the inverter efficiency rate to calculate the AC watt-hours ( Most of the inverters are about 90% efficient)**

`Battery AC watts = 600 * 90% = 540 AC watt-hours `

**4- Divide the battery AC watt-hours by the total load connected. **Let’s say 100-watt appliance is connected with your 100ah battery

`100ah battery runtime on 100w appliance = 540 / 100 = 5.4 hours`

**How long will a 100ah battery run an appliance that requires 100w?** 12v 100ah lead-acid battery with a 50% DoD limit will last about **5.4 hours** while running a 100-watt appliance.

## How Long Will A 100ah Battery Last? – Chart

Here’s a chart on how long will a 12v 100ah lithium (LiFePO4) battery will last while running a different watt load.

### How Long Will 100ah Lead-Acid Battery Last?

Appliance Power Required | 100ah Battery Runtime |
---|---|

20 watt | 27 hours |

40 watt | 13.6 hours |

50 watt | 10.9 hours |

60 watt | 9 hours |

100 watt | 5.5 hours |

150 watt | 3.6 hours |

200 watt | 2.7 hours |

300 watt | 1.8 hours |

400 watt | 1.3 hours |

500 watt | 1 hour |

600 watt | 54 minutes |

800 watt | 40 minutes |

1000 watt | 33 minutes |

1200 watt | 27 minutes |

1500 watt | 21 minutes |

2000 watt | 12 minutes |

3000 watt | 10 minutes |

#### Summary

- 12v 100ah lead-acid battery will last about
**11 hours**running a 50-watt appliance - 12v 100ah lead-acid battery will last about
**2 hours and 42 minutes**running a 200-watt appliance - 12v 100ah lead-acid battery will last
**21 minutes**running a 1500-watt appliance - 12v 100ah lead-acid battery will last about
**10 minutes**running a 3000-watt appliance

### How Long Will 100ah Lithium (LiFePO4) Battery Last?

Appliance Power Required | 100ah Battery Runtime |
---|---|

20 watt | 54 hours |

40 watt | 27 hours |

50 watt | 22 hours |

60 watt | 18 hours |

100 watt | 11 hours |

150 watt | 7 hours |

200 watt | 5.4 hours |

300 watt | 3.6 hours |

400 watt | 2.7 hours |

500 watt | 2.1 hours |

600 watt | 1.8 hours |

800 watt | 1.3 hours |

1000 watt | 1 hour |

1200 watt | 54 minutes |

1500 watt | 43 minutes |

2000 watt | 33 minutes |

3000 watt | 21 minutes |

#### Summary

- 12v 100ah lithium battery will last
**27 hours**running a 40-watt appliance - 12v 100ah lithium battery will last
**1 hour and 48 minutes**running a 600-watt appliance - 12v 100ah lithium battery will last
**1 hour and 18 minutes**running an 800-watt appliance - 12v 100ah lithium battery will last
**54 minutes**running a 1200-watt appliance

Note!The values are based on AC output load with a 90% efficient inverter.

## Assumptions & Shortcomings Of All These Methods

Here are some extra yet important points to keep in mind when figuring out how long will your 100ah battery will last running a load

### Battery Life Cycle Count:

- The storage capacity of the battery will decrease with every cycle ( a cycle is when you charge and discharge the battery to its DoD limit ).
- if you have used your battery for a few hundred cycles then the result will be different. ( this factor isn’t included in my above-given methods )

### Batteries Are Rated For 5 Amps Over 20 Hours Of Time:

- Especially lead-acid type batteries are designed to be discharged at 20 hours. ( means 100ah
**lead-acid batteries are recommended to be discharged @ 5 amps**in order to maintain the battery health and reduce the discharge efficiency ). - on the other hand,
**AGM and lithium (LiFePO4)**can be**discharged at 50% of their capacity**. - Discharging your battery at a higher rate will increase heat in the battery’s internal cells which will cause power loss. (this factor isn’t included in my above-given methods).
**For example**, if you discharge your lead-acid battery with 100 amps then it’s will not last 30 minutes ( keep in mind the 50% DoD limit ). but it may last about 10-15 minutes.- Check the battery discharge rate on the specs sheet of your battery or it’ll be mentioned on the battery
**(1h → 1C, 2h → 0.5C, 5h → 0.2C, etc.)**

## Related FAQ’s

**How long will a fridge run on a 100Ah battery?**

a 12v 100Ah lead-acid battery with 50% depth of discharge will run a small size camping fridge (2-5 cu. ft.) for about 18-24 hours and a large-sized kitchen fridge (20-25 cu. ft.) for about 6-8 hours

**How long will a 100Ah battery run a TV?**

a 100ah battery will run a Tv for about 10-50 hours. The exact value will depend on the size and type of television, and also the battery depth of discharge limit

**How many watts can a 100Ah battery run?**

You can safely run 600 watts on a 100ah lithium battery at a time and 120 watts on 100ah lead-acid battery

**How long will a 100Ah battery run a light?**

100ah lead-acid battery can run a 100 watt of lights for about **6 hours**

**What can I run off a 100Ah battery?**

100ah battery is equal to 1200 watt-hours and you can run almost any all kind of home appliances with it, like fridge, tv, charging phone, laptop, lights, etc…

**Is 100Ah enough for camping?**

100ah battery would be enough for camping to run most of the basic appliances like lights, charging phones and laptops, etc…

**how long will a 100ah lithium battery last**

100ah lithium battery will last 1 hour (running a 1200 watts DC of load) and 120 hours (running a 12 watts of DC load)

12v 100ah means **1200 watts**, 24v 100ah means **2400 watts**, 48v 100ah means **4800 watts**. To calculate the watts in a battery use this formula **( battery watts = battery amp-hours * battery volts )**

## Other Related Posts

- How Long To Charge 100Ah Battery? + Calculator
- How Long Does It Take To Charge A 100Ah Lithium Battery?
- How Long Will A 100Ah Battery Run A Tv? (+ Calculator)
- How Long Will A 100ah Battery Run A Fridge?
- What Size Inverter For 100Ah Battery?

## Resources

- Basics about battery Discharging – Battery University
- Discharge and battery capacity – Rebelcell
- Battery Discharge – an overview | ScienceDirect
- solar battery bank discharge explained – Sinovoltaics