Lawn mower batteries come in all shapes and sizes, which can make selecting the right one a confusing task. There are different size batteries, different connections, and this thing called CCA. Oh, and you also have to take into account what type of battery you need, such as an AGM or standard lead acid.
As you can see, getting the right lawn mower battery isn’t that straightforward, and selecting the wrong one can make a big difference. It will either work or it won’t. Therefore, let’s look at what these options mean and see which battery will work with your lawn mower.
Lawn Mower Battery Size Chart (An Overview of Different Batteries)
There are several specifications you need to match with your lawn mower’s needs when selecting a new battery for your mower. So I’ve created a lawn mower battery size chart showing the different specification requirements and some of the options available. Now I haven’t listed every option, as there are literally hundreds of options available. But this will give you a pretty good idea of what is available.
Lawn Mower Battery Size Chart
| Individual Battery Specifications | Options |
|---|---|
| Battery Physical Size (BCI) | U1 - 22 - 45 - 47 - 51 |
| Terminal Connection | SEA - Threaded - Lug - Side - Duel |
| Terminal Connection Position | L - R & Standard |
| Battery Design | AGM - Lead Acid |
| CCA | 120 - 200 - 230 - 300 - 350 - 480 - 500 |
Buying the Right Lawn Mower Battery Size + Type (My Top Tips)
How do you know which battery to buy for your lawn mower when there are so many options available? Well, you need to make sure that you match the battery to your specific lawn mower. So, let’s take a look at what each of these different specifications means and which ones will match your lawn mower.
Battery Physical Size (BCI)
Many lawn mowers have battery boxes to protect batteries from damage. However, these boxes are a particular shape and size and will only fit batteries of a specific size. So, there is a standard range (BCI standards) of lawn mower battery sizes. This means you’ll need to install a replacement battery of the same size.
For example, the John Deere S100, S200, and X300 lawn tractors all have space for a U1 battery. In contrast, the John Deere X500 and X750 lawn tractors both have space for a 51-sized battery. So, the first specification to check is the BCI battery’s physical size.
Terminal Connection
The next thing to check is the type of terminals your lawn mower uses to connect to the battery. Now, my riding lawn mower has a flat connector with a hole in its middle. This is called a lug connection, and it is where I use a nut and bolt to connect the cable to the battery terminal. When buying a new battery, you’ll want to make sure you get the right terminal connection so that you don’t have to make any modifications to your lawn mower battery cables.
Terminal Connection Position
If you look at the top of your lawn mower battery, you’ll be able to see where the cables are connected and what position they are in. Typically you’ll have one terminal in one corner on the left and the other terminal on the opposite corner on the right. But you might find both terminals are actually on the same side. This means you’ll need to purchase a battery to match.
For example, you might have a U1 battery with a lug style terminal with both terminals located on the left side, also known as a U1L Lug style.
Battery Design
The next item to check is the style of the battery. By this, I mean whether it’s a standard lead acid or an AGM. Now, this really comes down to cost and expectation. AGM batteries have better cycling and charging speed than standard lead acid, and they don’t leak when the lawn mower vibrates.
Now, for a guy that is just cutting his lawn once a week, this doesn’t make much of a difference. But professional lawn guys that start and stop their mowers all day at different properties need the guarantee of quick charging and leak-free batteries. So, the extra cost is well worth the money. Personally, I think you could save a few bucks and go for a standard lead acid battery if you have a home-use lawn mower.
CCA Cold Cranking Amps
Without going into too much technical detail, CCA is the number of amps required to start your lawn mower engine. Too few CCAs and your lawn mower won’t have the power to start. So how many CCAs should a lawn mower battery have? Well, this all comes down to the size of the engine and the design. The bigger the engine size, the more CCAs are needed.
For example, a twin-cylinder engine will need more CCAs than a single-cylinder engine. So, is there a standard amount of CCAs you need for a riding lawn mower? No. It really comes down to the engine and the CCA requirements stated by the lawn mower manufacturer.
Here are a few examples of various lawn mowers made by different manufacturers and the requirement of CCAs.
Lawn Mower Model CCA Requirements
| Brand | Model | Mower Type | Deck Size | Engine Size | CCAs |
|---|---|---|---|---|---|
| Cub Cadet | 5400 | Lawn Tractor | 42” | 541 | 230 |
| Cub Cadet | ZT1 | Zero-Turn | 54’’ | 726 | 210 |
| Troy Bilt | Pony | Lawn Tractor | 42” | 500 | 210 |
| Troy Bilt | Z54 | Zero-Turn | 54’’ | 725 | 210 |
| John Deere | S100 | Lawn Tractor | 42” | 500 | 300 |
| John Deere | Z700 | Zero-Turn | 54’’ | 726 | 340 |
As you can see, lawn mowers ranging from 500cc-541cc engines all require completely different CCAs. Even mower engines with a 725cc-726cc range have different CCA requirements. So, it’s down to what the manufacturer states.
FAQs When Buying Lawn Mower Batteries
Since I get a lot of questions about lawn mower battery sizes, I decided to put together some of the frequently asked questions. So here’s what people usually ask me.
Are All Lawn Mower Batteries the Same?
As you can see, lawn mower batteries are not all the same. There are actually hundreds of variations available. This means you can spec a battery to your lawn mower’s specific needs and power requirements.
Are Lawn Mower Batteries Standard or AGM?
Lawn mower batteries are available in both standard and AGM. Deciding which type of battery you use comes down to your personal preference.
Is a Lawn Mower Battery 6v or 12v?
New lawn mowers typically use 12v batteries. However, a few old models used to use 6v batteries, such as small walk-behind lawn mowers with electrical starters.
What Type of Battery Does a Riding Lawn Mower Use?
Gas-powered riding lawn mowers use 12v batteries. The specification of the 12v battery is based on the lawn mower’s needs and power requirements.
Where Do I Find the Battery Information For a Lawn Mower?
You can find the battery size and specifications printed on the existing battery installed in your lawn mower. In addition, you can look up the lawn mower battery specifications in the user manual or on the manufacturer’s website.
Can I Use a Battery With a Higher CCA?
It is fine to over-spec a lawn mower battery so that the battery has a higher CCA. Usually, a battery with a high CCA is more expensive. Therefore, it’s recommended to use the specified battery.
Why Might I Need Higher CCAs?
CCA is the calculation of a battery’s ability to crank an engine for 30 seconds at 0°F while maintaining at least 7.2 volts. The amps produced under these conditions are the CCAs.
So, for the typical person using a lawn mower just during the warmer cutting months, an increased CCA is not likely to provide any benefit.
But, for people who like to use their lawn mowers in cold weather, say for tasks like pulling a trailer or plowing snow, then a higher CCA will give their lawn mower better starting ability in the cold. If this is the case for you, then having a lawn mower battery with higher CCAs could prove valuable.
