In this post, you’ll learn how long will a 600ah battery last running a different size AC or DC load (with examples).
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.
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 600ah battery last
Solar Battery Runtime Calculator
Note! use my solar panel size calculator to find out what size solar panel you need to recharge your battery in desired hours with solar panels.
- 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 600
- 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 the battery last running a load.
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 600ah leisure battery last?
12v 600ah leisure battery with 50% DoD limit last about 3.2 hours running a 1000-watt AC load.
Batteries Connected in series or parallel?
If you have a total of 600ah battery capacity then I’m assuming that you have connected multiple batteries together.
if you’re a newbie remember these two main points when it comes to connecting different size batteries together.
- Parallel Connection: If two or more batteries are connected in parallel, the amps will add up but the voltage will stay the same (e.g 3x 12v 200ah batteries connected in parallel will be equal to 12v 600ah)
- Series connected: f two or more batteries are connected in series, the voltage will add up but the amps will stay the same (e.g 3x 12v 200ah batteries connected in series will be equal to 36v 200ah)
Video – All about battery basics (Must watch!)
Steps to calculate 600ah battery backup time
Follow these steps to calculate the battery life/runtime while running a load.
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 600ah battery
600ah battery in watts = 600 * 12 = 7200 watt-hours
2- Multiply the battery watt-hours by 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 = 7200 * 50% = 3600wh
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 = 3600 * 90% = 3240 AC watt-hours
4- Divide the battery AC watt-hours by the total load connected. Let’s say a 1000-watt appliance is connected to your 600ah battery
600ah battery runtime on 1000w appliance = 3240 / 1000 = 3.24 hours
How long will a 600ah battery last? – chart
Here’s a chart on how long will a 12v 600ah lithium (LiFePO4) and the lead-acid battery will last while running a different watt load.
How long will 600ah lead-acid battery last?
|Appliance Power consumption||600ah lead-acid Battery Runtime|
|50 watt||65 hours|
|100 watt||32 hours|
|150 watt||22 hours|
|200 watt||16 hours|
|300 watt||11 hours|
|400 watt||8 hours|
|500 watt||6.5 hours|
|600 watt||5.5 hours|
|800 watt||4 hours|
|1000 watt||3.2 hours|
|1200 watt||2.7 hours|
|1500 watt||2.1 hours|
|2000 watt||1.6 hours|
|3000 watt||1 hour|
- 12v 600ah lead-acid battery with 50% DoD limit last between 65 hours (running 50-watt AC load) to 1 hour (running 3000-watt AC load)
How long will 600ah lithium (LiFePO4) battery last?
|Appliance Power consumption||600ah lithium Battery Runtime|
|50 watt||130 hours|
|100 watt||65 hours|
|150 watt||43 hours|
|200 watt||32 hours|
|300 watt||22 hours|
|400 watt||16 hours|
|500 watt||13 hours|
|600 watt||11 hours|
|800 watt||8 hours|
|1000 watt||6.4 hours|
|1200 watt||5.2 hours|
|1500 watt||4.2 hours|
|2000 watt||3.2 hours|
|3000 watt||2 hours|
- 12v 600ah lithium battery with 100% DoD limit last between 130 hours (running 50-watt AC load) to 2 hours (running 3000-watt AC load)
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 600ah 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 )
600ah lead-acid Batteries are rated for 30 amps over 20 hours of time:
- Especially lead-acid type batteries are designed to be discharged at 20 hours. ( means 600ah lead-acid batteries are recommended to be discharged @ 30 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 600 amps then it’s will not last 30 minutes ( keep in mind the 50% DoD limit ). but it may last about 15-20 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.)
600ah battery is equal to 7200 watts @ 12v, 14,400 watts @ 24v, 28,800 watts @ 12v,
600ah battery will take about 8.8 peak sun hours to get fully charged from 50% depth of discharge with 600 watts of solar panels
You need about 1000 watts of solar panels to charge a 600ah battery from 50% depth of discharge in 5 peak sun hours.
other useful posts
- Solar Panel Size Calculator For Battery
- Solar DC Watts To AC Watts Calculator & Formula
- Solar Battery Charge Time Calculator + (Tips To Reduce Charge Time)
- Basics about battery Discharging – Battery University
- Discharge and battery capacity – Rebelcell
- Battery Discharge – an overview | ScienceDirect
- solar battery bank discharge explained – Sinovoltaics
i hope this guide was helpful to you if you have any queries Contact Us. Thank You!