What Battery for a 500-Watt Inverter

A 500-watt power inverter can run a variety of small appliances and electronic devices that operate at or below 500 watts of power consumption. The inverter converts direct current (DC) electricity stored in a battery into alternating current (AC) electricity that can be used to power these appliances and electronics.

The capacity of the battery will determine how much power your inverter can supply and how long it can power an appliance. In this article, we look at what you can run off a 500-watt inverter and what battery to use with the inverter. 

What can you run off a 500-watt Inverter?

A 500-watt inverter is meant to run appliances up to 500-watt max however it can support a continuous output somewhere between 400 watts. This is because of efficiency and conversion losses. Operating at 400 watts also ensures that the inverter does not overheat. 

A 500-watt inverter can run the following:

Refrigerator: A 200-watt refrigerator with a 400-watt surge. 

Blender: A 400-watt blender

Computer: A 200-300-watt desktop computer. 

It can also run several other devices including lights, laptops, mini-fan, phones, and TV. These appliances can also run on a 300-watt inverter. 

The actual runtime of the devices will depend on the capacity of the battery and the power requirements of the device being used. Let’s look at what size of battery you’ll need. 

What Battery Size for a 500-Watt Inverter?

The type and size of battery needed for a 500-watt power inverter will depend on several factors, such as the desired runtime, the load (devices/appliances) being powered, and the inverter’s efficiency. Let’s first take a look at the amp drawn from the battery. 

How Many Amps Does a 500-watt Inverter draw?

To calculate the amps required you divide the Watts by the voltage. The voltage in a battery bank is usually between 12v and 24v depending on how you wire the system. 

To find the size of the battery, you divide the watts by the voltage. 

For a 12v system, you’ll need 

500/12 = 41.67 Amps 

A 12-volt 500-watt should have a battery that can safely provide up to 33.33 amps of current. 

How many Amp-hours will you need?

Deep cycle batteries are recommended to be discharged at 0.2C or at 20% capacity. So for 41 amps, you’ll need a battery that is at least 200Ah battery. This battery can last up to 5 hours with the inverter. With a lead-acid battery with a 50% discharge, you’ll need a bigger battery of up to 300Ah battery to last as long. 

With a Lithium battery, you can use up to half of the capacity in an hour so you can actually use a 1000-watt-hour battery 80Ah Lithium battery. If you need this match power you can consider a 1000-watt Inverter.

Depending on how long you want to use your appliance you use up different capacities of the battery.

Time Power Requirements (Watts)Amps DrawBattery (12v)
1 hr40040200Ah
30 minutes250 21100Ah
20 minutes166 1365Ah
15 minutes1251150Ah

If you were using a blender for 15 minutes you won’t need as much power a 50Ah battery will be enough. 


To determine the battery capacity, you need to consider the power consumption of the devices that will be connected to the inverter and the expected duration of use. The battery capacity should be able to provide enough power to run the connected devices for the desired amount of time without draining the battery completely. For a 500-watt inverter, you can use a 12-volt deep cycle battery between 50Ah to 200Ah depending on the load from the appliances.

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