Batteries for standby generators are usually lead-acid batteries. These batteries are designed to provide power for a short period of time, and their capacity is typically measured in amp-hours (Ah). Many available batteries are available for standby generators, but all are not created equally. So, choosing the right one for your needs is important.
The best battery for standby generators is specially designed for supplying continuous electrical power. It has a long life span and can provide reliable power even during a power outage. This battery is made from high-quality materials and is designed to withstand extreme conditions. It is also maintenance-free and can be used for many years.
At a Glance:
Why is it Important to have a Battery When Using a Standby Generator?
There are a few reasons why having a battery is important when using a standby generator.
- First, if there is a power outage, the battery will help keep the generator running until utility power is restored.
- Second, if the generator is turned off for any reason, the battery will provide power to keep essential systems running until the generator can be restarted.
- Finally, batteries help protect sensitive equipment from voltage fluctuations and power surges.
With so many alternatives on the market for the search, choosing the correct starting battery for your Generac generator can be a difficult task.
Generac 5819 Model 26R Wet Cell Battery:
Best Pick
Brand | Generac |
Item Weight | 0.01 Ounces |
Voltage | 12 Volts |
This battery is a perfect replacement for the Generac model 26R battery. This reliable battery can start a 20 HP engine with ease of search if you want to buy. It has a sturdy design that makes it capable to power heavy appliances or devices for an extended period of time.
The automatic voltages regulator in this battery helps in maintaining a consistent voltage level of Generac generator models and prevents any damage to the battery or the device. This Wet Cell Battery is also spill-proof and leak-proof making it a safe option to use.
Features:
- The battery is black.
- The size is 26R.
- Its voltage is 12 volts.
- The dimension of the battery is 2 by 2 by 2 inches.
Why Buy This Product?
This battery is a perfect replacement for the Generac model 26R battery. It features a durable design that allows it to run large appliances or devices for long periods of time.
Pros
- Sealed lead-acid type
- It has a reliable design
- If it’s a home standby type it’s first with 22kw
Cons
- None
Interstate Batteries 12V 55AH SLA/AGM Deep Cycle Battery:
Staff Pick
Brand | Interstate Batteries |
Vehicle Service Type | ATV, Scooter |
Size | 12V 55AH – Insert Terminals |
Voltage | 12 Volts |
Battery Cell Composition | Sealed Lead Acid |
Item Weight | 37 Pounds |
Item Dimensions LxWxH | 9.02 x 5.43 x 8.27 inches |
Number Of Cells | 6 |
Terminal | Insert Terminal |
This is a 12V 55AH SLA/AGM deep cycle battery, and AGM technology has revolutionized the way we use batteries. Interstate Batteries is one of the best in this category. This type of battery is leak-proof and spill-proof, making it a safe option to use in any situation. If you have to install it, you can search for commercial installation as well.
This Deep Cycle Battery generator is perfect for vehicles with high capacities like ATVs, alarm systems, golf carts, and scooters.
Features:
- The batteries are black.
- The product dimensions are 9 by 5.5 by 8 inches.
- It comes with safety features.
- The brand is Interstate Batteries like sealed lead acid type.
Why Buy This Product?
This is ideal for vehicles that require a high-performance 12-volt deep cycle battery, such as ATVs, golf carts, and scooters. It is protected from damage by a robust outer casing, which makes it exceptionally durable and provides the highest battery performance.
Pros
- This is a 12-volt battery
- It weighs 39.3 pounds
- You can easily remove its handles
- It is maintenance-free
Cons
- It doesn’t have a warranty
200W Peak Power Station, Flashfish CPAP Battery:
Budget Pick
Brand | FF FLASH FISH |
Wattage | 150 watts |
Item Dimensions LxWxH | 8.3 x 4.7 x 7.1 inches |
Item Weight | 4.5 Pounds |
Color | 166Wh |
Voltage | 110 Volts |
Frequency | 60 Hz |
Ignition System Type | Electronic |
This is a 200W peak power station that can be used to power up CPAP machines, laptops, and other electronic devices. This is perfect for people who are looking for emergency backup system generators. It has a 166Wh portable capacity and comes with two 110V AC outlets like air-cooled generators.

This battery has a two-year limited warranty and a one-year usage period. The dimensions are 8.45 x 4.77 x7.09, and the product is 4 pounds. During comparison with similar devices, reviewers noted that these batteries fit very well in most machines and are also easily installed if you choose to do so with the built-in DC or USB ports that can connect to many other appliances.
Features:
- VRLA technology.
- It is protected from overcurrent, high voltages, low voltage, short circuits, and overheating with liquid-cooled padding.
- No Maintenance is required with the effectiveness of performance.
Why Buy This Product?
The Flatfish CPAP battery is a great emergency backup system for people who need to power their CPAP machines. It has a rechargeable battery that can be charged in less than 5 hours.
Pros
- The wattage of the battery is 150 watts
- Users confirmed its durability
- You can charge it in three ways
- It is very portable
Cons
- The batteries are a bit heavy
Weize 12V 18AH Battery:

Number of Batteries | 1 12V battery required. |
Brand | WEIZE |
Battery Cell Composition | Lead Acid |
Recommended Uses For Product | Scooter, Wheelchair |
Unit Count | 1 Count |
This is a 12V 18AH battery that works and operates perfectly. The brand is WEIZE and it needs one battery to function with many benefits.
The Weize has dimensions of 7 by 2.75 by 3.5 inches and weighs 5.5 pounds which makes them smaller than other batteries in the market, thus they are ideal for use in small spaces like wheelchair vans or scooters It comes with a capacity guarantee that lasts for a period of 2 years from its manufacturer.
Features:
- The battery is rechargeable.
- Its voltage is 12 volts.
- A 10.56 pounds is fair.
- Its wattage is 216 watts.
Why Buy This Product?
The machine pack is a perfect fit for the yard and garage where there are people who use scooters or wheelchairs. You will need one 12 volts 18 amp-hour energy storage system to run the generator, which is included in the standard package.
Pros
- It has an amperage of 18 amps
- You can use it for multiple purposes
- Its Amazon rating is 4.6 stars
- It is approved by TUV, CE, UL, ROHS, PSE, and FCC
Cons
- The batteries have a limited 10-month warranty
ML18-12 12V 18 AH SLA Battery:

Brand | Mighty Max Battery |
Battery Cell Composition | Sealed Lead Acid |
Unit Count | 1 Count |
Voltage | 12 Volts |
Reusability | Rechargeable |
The Mighty Max ML18-12 is a 12V battery that can either be used as an uninterrupted power supply or a deep cycle battery. It comes from the manufacturer known for its high quality, durable products and is has been tested rigorously to guarantee superior performance.
The top approval ratings that it holds are TUV, CE, UL, ROHS, PSE, and FCC approval which means you may not need to request additional certifications before installing in your state if the certification requirements differ from those listed here.
Features:
- It comes with a 1-year warranty.
- And it is rechargeable.
- Its voltage is 12 volts.
- Maintenance-free.
Why Buy This Product?
The Battery is rechargeable and versatile in performance. It can be used for a number of applications, comes with a 1-year warranty, and is maintenance-free. This battery is an excellent choice for those looking for a quality product.
Pros
- Users have given it an Amazon rating of 4.6 stars
- It is black in color
- It has an amperage of 18 amps
- Having 11.9 pounds isn’t bad
Cons
- Don’t work well in low temperatures
ExpertPower EXP12180 12V 18Ah Sealed Lead Acid Battery:

Number of Batteries | 1 12V battery required |
Brand | ExpertPower |
Battery Cell Composition | Lithium Metal |
Unit Count | 1 Count |
Voltage | 12 Volts |
This battery is perfect for the backup power needs of generators. It is made of lithium electrolyte metal and at the same time includes 12V.

The EXP12180 is Shock, Vibration, and Chemical Resistant. It has a rugged, go-anywhere design that fits easily in your hand, yet it weighs only 2.2 pounds (not including batteries. The product is user-friendly, durable, and rugged. It has the best Amazon rating of 4.5 stars, which crowns it all.
Features:
- Easy to use.
- The battery has a dimension of 7.13 by 3.03 by 6.57 inches.
- It is resistant to shock, chemicals, heat, and vibration.
Why Buy This Product?
This is a high-quality, dependable, and long-lasting battery that is ideal for standby power applications. It is one of the best batteries for standby generators since it is safe to use.
Pros
- Rechargeable
- It has a voltage of 12 volts
- It is made of lithium metal
- The batteries are backed by a maintained warranty of 18 months
Cons
- None found
Interstate Batteries Generac Generator Replacement Battery:

Number of Batteries | 1 12V battery required |
Brand | Interstate Batteries |
Battery Cell Composition | Sealed Lead Acid |
Compatible Phone Models | Iphone5s, iPhone 5 |
Recommended Uses For Product | Generators, Backup Systems, Cranking Systems |
This is a 12V 18AH for Generac generators. The batteries have an amperage of 18 amps and are black in color. One of the units is 10 pounds, and it comes with a one-year warranty against defects.
The product dimensions are 7 by 3 by 6 inches. It consists of 1 unit only and has no compatibility issues. The company has a good reputation and is one of the leaders in the battery industry of air-cooled Generac generators.
Features:
- It is maintenance-free.
- Dimension of 94 by 2.56 by 3.70 inches.
- It is durable with reasonable battery life.
- Users have given it an Amazon rating of 4.6 stars.
Why Buy This Product?
This product is affordable and comes highly recommended by most who have purchased it. The battery also seems to adapt well with other products as it has been proven to fit with other models as well, including the Coleman which is a very popular brand. It also works well in many different applications and can be used for various needs, such as with generators or power tools.
Pros
- The batteries offer 12 volts
- Its wattage is 36 watts
- And it has 5.62 pounds
- You can use it to power numerous appliances systems already installed
Cons
- The company offers only a one-year warranty
ExpertPower 12v9ah Generator Battery:

Brand | ExpertPower |
Vehicle Service Type | Street-touring-motorcycles, ATV, Scooter, Street-cruiser-motorcycles |
Size | YTX9-BS |
Voltage | 12 Volts |
Battery Cell Composition | Lead Acid |
item Dimensions LxWxH | 5.9 x 3.3 x 4.2 inches |
These are 12V 9AH batteries for motorcycles, street-cruiser motorcycles, ATVs, and scooters. The ExpertPower 12v9ah is made of lead-acid and has dimensions of 5.9 by 3.3 by 4.2 inches. It weighs 5.44 pounds and offers a voltage of 12 volts. The battery is backed by a warranty of 6 months. It does not require any maintenance.
The battery is powerful and long-lasting and has nut and bolt terminals attached to handle extreme conditions. Overall, it has an excellent Amazon rating.
Features:
- It has the harsh weather condition facing ability.
- And its amperage is 9 amps.
- Storage capability.
Why Buy This Product?
This battery is one of the most powerful and lasting batteries ever made, which is perfect for motorcycles, scooters, ATVs, and even cars. If you need a good power source or a high capacity to replace or upgrade your current battery mechanism on any of your vehicles that run with motor power, this is the one for you.
Pros
- You’ll like its 1-year warranty
- The battery is rugged and durable
- Spill-proof
Cons
- No longer service life
A Quick Shopping Tips – Best Standby Generator Battery:
When looking for a battery for your standby generator, it is important to keep in mind that not all batteries are created equal. Here are a few tips to help you choose the best battery for your needs:

Reusability:
A deep cycle battery is designed to be discharged down as much as 80% many times and charged back up. This type is best usually when you want a home standby generator battery.
Long-Lasting:
The deep cycle battery should last 2-3 years under normal use (for your standby generators). After that, it will need replacing.
Power:
The inverter/charger in the standby generators will reduce the power coming off the alternator. The inverter should be sized based on how much power you’ll ‘consume’ at one time, not how often it needs to run. There are online sizing calculators that can help with this.
Charging:
The best batteries for a generator charging system should be sized to match the deep cycle models. The charger will use a lot of power in either case so it needs to not be oversized, otherwise, your standby generator will run out of gas.
Proper Storage:
The battery needs to be changed monthly, so plan on at least a monthly visit from the generator. If the deep cycle battery is allowed to discharge down below 50% too many times it won’t last as long, and if it sits for a long time without being charged, it can burst.
Same Power Rating Compatibility:
Not all batteries are compatible with inverters, so you’ll need to check that before buying one.
Weight:
The battery should be as light as possible for an easier installation of power outages.
Conclusion:
The batteries we’ve looked at are the latest standby generator batteries. We decided to try them out and once we did, we were very pleased with their performance, especially for the best rated Generac 5819 Model 26R Wet Cell Battery. Based on our experience, we can certainly say that you’ll be getting the best value for your money. We’re confident in what we recommend because, after our test period, we found that all of these products stand well above their competitors. That said, you can trust what we tell you about any product especially when it comes to generators.
Frequently Asked Questions:
What is the Best Battery for a Standby Generator?
The Generac 5819 Model 26R Wet Cell Battery is the best battery for a standby generator. It’s a maintenance-free, deep-cycle battery that is designed to deliver reliable power in a home standby generator application. This battery has high cranking amps and reserve capacity, so it can provide the power you need when you need it most.
How Often Should you Replace the Battery in your Standby Generator?
Typically, a standby generator’s battery will need to be replaced every three to five years. However, this can vary depending on the make and model of the generator as well as how often it is used. If you use your generator frequently, you may need to replace the battery more often. Conversely, if you only use it occasionally, you may be able to stretch the lifespan of the battery a bit longer.
What Voltage of a Battery Do I Need for a 22kW Generator?
The voltage of a battery for a 22kW generator depends on the particular generator model. Typically, the voltage required is 120/240 Volts capacity.