Best 12V, 24V, 36V, and 48V Lithium Deep Cycle Battery For a Power Inverter

Power inverters convert DC power from the batteries into DC/AC power, allowing the users to use home appliances, tools, and other AC devices when AC power is not present during emergencies, blackouts, or simply while being off the grid.

Lithium deep cycle batteries are almost ideal battery type for such application since they tolerate deep discharge applications, support a large number of charging/discharging cycles, are lightweight, can be easily recharged, etc.

Updated: October 24, 2024.

Lithium Inverter Batteries

Lithium inverter batteries have a nominal voltage of 12V, 24V, 36V, and 48V, with the most popular being 12V deep cycle lithium batteries.

When looking for the "best" battery, it is important to know a few things about the power inverters themselves, including:

• nominal input voltage: input voltage is usually 12V, 24V, 36V, and 48V, although there are power inverters with even higher input voltages,
• nominal output power is given in Watts, and it is the maximum output power that the power inverter can provide continuously,
• maximum output power is given in Watts, and it is the maximum output power that the power inverter can provide for short periods of time (seconds, for example),
• energy efficiency: power inverters are not ideal electronic devices and some energy during conversion is lost in the form of heat. Good power inverters feature energy efficiency up to 90%, although just to be safe, when crunching numbers, use 80% efficiency at most.

There are other very important features of modern power inverters, but when looking for the best lithium power inverter batteries, these power inverter features are the most important ones.

Deep cycle lithium batteries are mostly Lithium Iron Phosphate (LiFePO₄) batteries with built-in Battery Management Systems (BMS), protecting the batteries from unwanted events like high/low voltage, high/low temperature, short circuit, and similar.

When looking for the "best" battery, it is important to check a few details first, including:

• nominal and actual voltage: nominal voltage of the 4-cell LiFePO₄ batteries is 12V, and the actual voltage is 12.8 volts. Similarly, 8-cell LiFePO4 batteries feature a nominal voltage of 24V and an actual voltage of 25.6 volts, etc. When being discharged, lithium batteries hold their output voltage most of the time around 12.0 - 12.8 volts (or 24.0 - 25.6 volts), with some models providing 12+ (24+) volts at least 90% of their discharge time, unlike lead-acid batteries which quickly drop below 12V (or 24V, 36V, 48V, depending on the battery setup).
• when being discharged with strong currents, lithium batteries capacity is not decreased like the capacity of lead-acid batteries.
• maximum continuous discharge current of the deep cycle lithium batteries is limited by the BMS and is usually around 1.0C.
• maximum surge discharge current of the deep cycle lithium batteries is limited by the BMS and is very often around 2C for few seconds, after which the BMS disconnects the battery unless the discharge current is decreased.
• connecting in series and parallel: lithium batteries can be connected in series and parallel only if it is explicitly allowed by their manufacturer. Even then, the batteries should be connected as recommended by the manufacturer.

12V Lithium Deep Cycle Inverter Batteries

The following chart lists some of the most popular 12V lithium batteries with their most important features and specifications:

Note: Amazon affiliate links ("Model" column) open in the new windows - feel free to check them for the most up to date offers and prices.

As one can see, 12V lithium deep cycle batteries differ in both size, shape, their nominal capacity, and especially their discharge currents and their ability to be connected in series and parallel, safely.

Little Bit of Math

Example 1:

If we have a 12V 1000W power inverter with 90% energy efficiency, and if we want to power it for at least 40 minutes with a single 12V battery, what is the minimum recommended capacity of the lithium deep cycle battery?

First of all, let's calculate the required current.

If the output power is 1000W, input power is 1000W/0.9= ~1110 watts.

If the input power is 1110 watts @12V, what is the required current?

I = 1110W/12V = 92.5 Amps

If we check the 12V lithium battery chart, lithium 12V 100Ah or larger batteries are able to provide at least 92.5 Amps continuously.

Also, they are also able to provide 92.5 Amps for at least an hour, which is better than the required 40 minutes.

Example 2:

If we have a 12V 200Ah lithium battery and want to power the 80% energy efficient inverter with a 500W load, how long will the battery last?

Input power is 500W/0.8 = 625 watts, meaning that the discharge current is 625W/12V = ~52 Amps.

12V 200Ah lithium battery can provide such power for almost 200Ah/52A = 3.84h = ~ 3h 50 minutes.

The actual time depends on the battery condition and its initial charge.

In order to decrease the currents and increase the efficiency in general, some power inverters use 24V, 36V, and 48V batteries.

24V Lithium Deep Cycle Inverter Batteries

The following charts list some of the most popular 24V, 36V, and 48V lithium deep cycle batteries that are suitable for use as inverter batteries. The 24V lithium batteries are given in the following chart:

Note: Amazon affiliate links ("Model" column) open in the new windows - feel free to check them for the most up to date offers and prices.

While a 24V battery pack can be made using a pair of the 12V lithium batteries connected in series, having a single battery can help the user keep things as simple as possible.

36V Lithium Deep Cycle Inverter Batteries

The following chart lists some of the most popular 36V lithium batteries with their most important features and specifications:

Again, while a 36V battery pack can be made using three of the 12V lithium batteries connected in series, having a single battery can help the user keep things as simple as possible. Also, by tripling the voltage, the current is also decreased 3 times.

48V Lithium Deep Cycle Inverter Batteries

The following chart lists some of the most popular 48V lithium batteries with their most important features and specifications:

48V batteries can be created by connecting 4 (four) 12V batteries or 2 (two) 24V batteries in series. Or, to keep things simple, the user can pick the most suitable 48V battery (or batteries).

Are Lithium Deep-Cycle Batteries Better Than Lead-Acid Batteries For Inverters?

Yes, lithium deep cycle batteries are generally better than lead-acid batteries for use with power inverters due to several key advantages:

• Longer lifespan: Lithium batteries can last up to 10 times longer than lead-acid batteries, reducing the need for frequent replacements.
• Higher energy efficiency: Lithium batteries have a higher energy efficiency, which means they can provide more energy than lead-acid batteries for the same amount of energy received during the charging process.
• Deeper discharge: Lithium batteries can be discharged up to 80-90% of their capacity without damaging the battery, while lead-acid batteries are typically limited to 50%.
• Faster charging: Lithium batteries charge faster than lead-acid batteries, which can reduce downtime.
• Maintenance-free: Lithium batteries require little to no maintenance, unlike lead-acid batteries, which need regular maintenance, such as checking water levels.
• Consistent power output: Lithium batteries maintain a stable voltage level even as their charge level drops, providing more reliable power to inverters.

Although lithium batteries are more expensive upfront, their longer lifespan, efficiency, and low maintenance make them a more cost-effective choice over time compared to lead-acid batteries.

Can Lithium Deep Cycle Batteries Handle High Loads From Power Inverters?

Yes, lithium deep-cycle batteries are well-suited to handle high loads from power inverters. Here’s why:

• High discharge rate: Lithium batteries can deliver higher continuous and peak discharge currents, which means they can handle large power demands from devices connected to the inverter without dropping voltage significantly.
• Consistent voltage output: Lithium batteries maintain a stable voltage output even under high load conditions, ensuring that power inverters can operate efficiently and deliver consistent power to devices.
• Low internal resistance: Lithium batteries typically have lower internal resistance than lead-acid batteries, allowing them to supply power more efficiently and handle high loads without overheating or energy loss.
• Temperature tolerance: Many lithium batteries are designed to operate at a wider temperature range, making them reliable under various conditions when high power is needed.
• Extended lifespan under high load: Lithium deep cycle batteries can endure more charge and discharge cycles even when subjected to high power demands, unlike lead-acid batteries, which degrade faster under similar conditions.

This makes lithium batteries an ideal choice for inverters handling high-load appliances or systems. However, it's important to ensure that the battery's rated capacity and specifications match the power inverter's requirements.

Long Story Short: Lithium deep cycle batteries are ideal power inverter batteries - they initially cost more than lead-acid batteries of the same capacity, but they are lighter, they support much more charging/discharging cycles, their capacity doesn't decrease with the increase in discharge current, etc.

Although these batteries are protected by BMSs, they are nonetheless able to provide very strong currents that can cause damage, injuries, or worse. Thus, safety first ...