Your Generac 22kW generator is a critical investment in your home’s safety and comfort, designed to kick in automatically during a power outage. The heart of this reliable system is its battery, which provides the necessary jolt to start the engine. Choosing the right battery and supporting accessories is not just about maintenance—it’s about ensuring your generator performs flawlessly when you need it most, especially during extreme weather conditions.
This guide simplifies your search by reviewing eight top-rated batteries and essential cold-weather kits compatible with your Generac 22kW unit. We’ve evaluated options based on performance, durability, and specific features to help you make an informed decision. From robust GEL batteries to innovative lithium options and vital heating pads, you’ll find the perfect component to keep your backup power system in peak condition year-round.
Our Recommended Batteries and Accessories
- Mighty Max Battery 12V 35AH GEL Replacement
- Cold Weather Kit for Generac- Battery Warmer Pad
- Mighty Max Battery 12V 9AH Battery Replacement
- Generac Guardian 22kW Home Standby Generator
- Generac 7101 Battery Heater Pad
- NOCO Lithium NLP30: Ultra-Light 12V Lithium
- Mighty Max Battery ML35-12 – 12V 35AH
- ExpertPower EXP12300 Rechargeable Lead Acid
Mighty Max Battery 12V 35AH GEL Replacement Battery
The Mighty Max ML35-12GEL is a robust, maintenance-free GEL battery designed as a direct replacement for your Generac unit. Its GEL cell technology offers a significant advantage with a slower self-discharge rate, meaning it holds its charge for longer periods between uses compared to standard AGM batteries. This makes it a reliable choice for a standby generator that may sit idle for extended times.
Built to perform in a wide range of environments, this battery provides consistent power delivery even in extreme temperatures. Whether facing the intense heat of summer or the freezing conditions of winter, its resilience to temperature fluctuations ensures your generator receives a solid starting power. This durability makes it a superior upgrade for homeowners looking for long-term reliability.
Cold Weather Kit for Generac- Battery Warmer Pad
This comprehensive cold weather kit is an essential accessory for protecting your generator in freezing climates. It includes both a UL-certified battery warmer pad and an oil heater pad, providing thermostatic control to reduce battery power loss and ensure oil remains at a functional viscosity. This dual-heating approach is vital for maintaining generator safety and readiness during cold snaps.
Compatible with 9kW to 22kW air-cooled Generac models manufactured in 2008 or later, this kit automatically activates when temperatures drop to 40°F (4°C) and turns off at 55°F (13°C). You never have to worry about manually turning the heaters on, as the system provides continuous, automated warmth to optimize performance and extend the overall life of your generator.
Mighty Max Battery 12V 9AH Battery Replacement
This Mighty Max battery is a UL Certified, 12V 9AH Sealed Lead Acid (SLA) battery that serves as a reliable replacement for specific Generac portable generators. Its spill-proof design and maintenance-free operation make it a hassle-free solution. The battery is characterized by a high discharge rate, which is essential for providing the sudden burst of power needed to start an engine.
With its ability to operate across a wide temperature range and its long service life, this battery is built for consistent performance. The compact dimensions ensure a proper fit, and it comes with nut and bolt terminals for a secure connection. It’s a straightforward, dependable power source for keeping your portable generator ready for action.
Generac Guardian 22kW Home Standby Generator
While not a battery itself, the Generac Guardian 22kW is the complete system your battery supports. This automatic whole-house backup power solution runs on natural gas or liquid propane and includes a 200 Amp transfer switch for seamless operation during storms and outages. Its integrated Mobile Link Wi-Fi capability allows for remote monitoring from anywhere, giving you real-time status updates and maintenance alerts.
This generator provides comprehensive protection for your home, ensuring that essential appliances and systems remain operational during a power interruption. The system is built for long-term reliability and is backed by a 5-Year Limited Warranty, offering significant peace of mind for your investment in home security and comfort.
Learn More About This Generator
Generac 7101 Battery Heater Pad
The official Generac 7101 Battery Heater Pad is a focused solution for maintaining your battery’s performance in cold weather. It is engineered to fit perfectly under the generator battery and automatically activates when temperatures fall below 40 degrees Fahrenheit. By providing consistent warmth, it helps prevent the power loss and starting failure that cold batteries often experience.
This genuine Generac part is compatible with air-cooled standby generators manufactured in 2008 or later. Its automatic on/off function centered around 40°F to 55°F ensures your battery remains at an optimum temperature without any manual intervention, safeguarding its ability to start the generator reliably throughout the winter.
NOCO Lithium NLP30
The NOCO NLP30 represents a modern leap in battery technology with its ultra-lightweight 12V lithium design. It offers exceptional starting power, delivering over 700 amps—significantly more than traditional lead-acid batteries. This results in up to 10 times more starts and a lifespan that is five times longer, making it a high-performance, long-term investment.
This battery is completely maintenance-free, with no risk of sulfation or acid leaks. It includes an intelligent Battery Management System (BMS) that actively protects against overcharging, short-circuits, over-discharging, and extreme temperatures. For homeowners seeking the most advanced and reliable starting power available, the NLP30 is a compelling option.
Mighty Max Battery ML35-12
The Mighty Max ML35-12 is a 12V 35AH U1 Sealed Lead Acid (SLA) battery, offering a reliable and cost-effective power solution for your Generac generator. As a sealed battery, it is spill-proof and can be mounted in various positions without risk of leakage, providing flexibility during installation. Its construction is designed for a long service life with minimal upkeep.
This battery provides the consistent cranking amps required for dependable generator starts. It’s a solid, maintenance-free choice that balances performance and value, making it a popular replacement option for homeowners who need a trustworthy battery without complexity.
ExpertPower EXP12300 Rechargeable Lead Acid Battery
The ExpertPower EXP12300 is a 12V 30AH rechargeable lead-acid battery built for deep-cycle applications, which can also serve as a robust starting battery. It is engineered for resilience, capable of handling repeated discharge and recharge cycles. This makes it a durable option that can withstand the demands of a standby power system.
Users can expect stable performance and a long operational lifespan from this maintenance-free battery. Its sealed design ensures safe operation and easy handling, providing a dependable power reserve that ensures your generator is prepared to activate whenever the main power fails.
Buying Guide: How to Choose the Best Batteries for Generac 22kW Generators
When my power goes out, I need my Generac 22kW generator to start on the first try, no questions asked. The heart of that reliable start is the battery. I have learned that not just any battery will do; you need one that matches the demands of your home standby system. The first thing I always check is the group size. For most Generac 22kW models, you are looking for a Group 26R or sometimes a Group 35 battery. This refers to the physical dimensions, terminal location, and type. Grabbing the wrong group size is a quick way to end up with a battery that does not fit the tray.
Next, I look at the Cold Cranking Amps (CCA). This is a measure of the battery’s ability to start an engine in cold temperatures. Since generators often need to kick on during winter storms, a high CCA rating is non-negotiable. I aim for a battery with at least 500 CCA to ensure it has enough power to turn the engine over, even on the coldest nights. Alongside CCA, consider the Amp Hour (Ah) rating, which tells you about the battery’s capacity—how long it can provide a steady current. A higher Ah rating can be beneficial for longer cranking times or if you have any parasitic draws on the system.
The type of battery technology is another big decision. The standard, and most common, is the flooded lead-acid battery. They are affordable and reliable but require occasional maintenance, like checking and topping off the water levels. Then you have Absorbent Glass Mat (AGM) batteries. These are my personal favorite for generator use. They are completely sealed, spill-proof, require zero maintenance, and are better at handling vibration and temperature extremes. They also have a lower self-discharge rate, meaning they hold their charge longer while sitting idle. While AGM batteries cost more upfront, the peace of mind and convenience are worth it for me. When selecting from the 8 best batteries for Generac 22kW generators, I prioritize a maintenance-free AGM design with a robust CCA rating to guarantee my home stays powered no matter what.
Frequently Asked Questions
What is the official Generac battery part number for a 22kW generator?
Generac typically recommends their own branded battery, part number 0G1886. This is a Group 26R, maintenance-free battery that is a direct fit for many of their 22kW models. However, many aftermarket batteries from reputable brands like Duracell, Deka, and Odyssey in the same group size will work perfectly and might offer different specifications or a better price point.
Can I use a regular car battery in my Generac generator?
I strongly advise against it. While a car battery might physically fit and seem to work, it is not designed for the same purpose. Generator starting batteries are built for a very different duty cycle. They need to provide a large burst of power to start the engine and then sit for long periods while being kept at a full charge by the generator’s charger. Car batteries are designed for shallow cycles and frequent charging from an alternator. Using one can lead to premature failure and leave you without power when you need it most.
How often should I replace the battery in my generator?
A good rule of thumb I follow is to replace the battery every 3 to 4 years. Battery life can vary based on climate, maintenance, and how often the generator runs. Living in an area with extreme hot or cold temperatures can shorten a battery’s lifespan. Even with a maintenance-free battery, I test its voltage and CCA output at least once a year as part of my generator’s routine maintenance to avoid any surprises.
Why does my generator battery keep dying?
There are a few usual suspects. The most common is that the battery is simply old and can no longer hold a charge. The second is an issue with the generator’s built-in battery charger. If the charger fails, the battery is not being topped off and will slowly drain. Finally, if you have a newer, smart charger on your generator, it needs to see a good battery to initiate a charge. A deeply discharged or dead battery might not be recognized, creating a cycle where it never gets charged.
Is an AGM battery better than a flooded battery for my generator?
For most homeowners, I believe an AGM battery is the superior choice. The key advantage is that it is completely maintenance-free—no need to ever check water levels. AGM batteries are also more resistant to vibration, spill-proof, and generally have a longer lifespan and faster recharge rate than comparable flooded batteries. While they cost a bit more, the reliability and hands-off operation make them one of the best batteries for Generac 22kW generators you can buy.