How to Charge the Battery on a Riding Lawn Mower

Are you having trouble getting your lawn mower started? A dead battery may be your problem. Like cars, lawn mowers require maintenance, and sometimes that involves recharging the battery. Luckily, there are a couple of easy ways to do this at home. Follow these steps on how to charge a lawn mower battery with or without a charger.

Before you get started

To ensure a successful charge, ask yourself these three questions.

1. What voltage is a lawn mower battery?

Most lawn mowers built after 1980 use 12-volt batteries—double-check your model to be sure. The voltage of your mower battery charger should match the number of volts in your battery. Check the number of amps in your lawn tractor battery charger, too. Ten amps are standard, and anything lower is also ok — anything higher than 10 amps may hurt the battery.

2. How often does a lawn mower battery need charging?

Lawn mower batteries tend to last a while, so you don't need to charge on a regular basis. It's more likely to die if the mower is out of use for an extended period or if you accidentally leave the keys in the ignition for several hours.

If you live in a cold climate and store your lawn mower during the winter, you may need to recharge the battery at the start of spring. However, you can decrease those chances by fully charging the battery before putting the mower into storage. Check out our guide on other ways you can prep your lawn maintenance equipment for the spring season.

3. How long does it take to charge a lawn mower battery?

The amp level on your mower battery charger determines how quickly it will charge. A standard 10-amp charger takes about an hour to reach a full charge; that number decreases for smaller amp values. For example, a five-amp charger will charge your lawn mower battery in about two hours.

How to charge a lawn mower battery with a charger

If you have a lawn mower battery, follow these steps for an easy charge.

1. Put on safety gear. Wear gloves and protective glasses anytime you're handling a lawn mower battery or jumper cables. They'll keep you protected in case there's a spark.
2. Access the battery. The battery on most ride-on lawn mowers is located under the seat. You can leave the battery there while charging — there's no need to remove it.
3. Connect the charging cables. Connect the charger's red cable to the positive battery terminal and the black cable to the negative battery terminal.
4. Set the voltage and amp level. Some lawn tractor battery chargers let you adjust the voltage and amp level. Make sure the voltage matches your battery's voltage — most likely 12 — and set the amp level to 10 or less.
5. Plug in the charger. Plug the charger into a wall outlet to juice up the battery.
6. Disconnect when the battery is full. A 10-amp charger takes about an hour; expect longer for smaller amp levels.

How to jump-start a lawn mower with a car

Don't have access to a mower battery charger? If your mower uses a 12-volt battery, you can safely jump-start it with your car. Some chemicals and vapors may be released when using this method, so wear gloves and protective glasses and do this in a well-ventilated area, preferably outdoors. After taking these precautions, follow these steps:

1. Turn the car engine off. Pull the car right up to the lawn mower and turn off the engine. Leaving the engine on may cause the mower battery to overheat.
2. Connect the jumper cables. Connect one end of the red cable to the positive terminal on your lawn mower battery and the other end to the positive terminal on your car battery. Plug the black cable onto the negative battery terminal on each.
3. Start the lawn mower. Once the cables are connected, start the lawn mower. If it doesn't start right away, let it sit for a minute or two while connected to the car.
4. Disconnect the jumper cables. With the lawn mower running, disconnect the jumper cables and remove the key from your car's ignition. (You don't want a dead battery there next.)
5. Leave the lawn mower running for an hour. This will activate the mower's alternator, refilling the battery. After that, you can head out to cut the grass or turn the engine off, knowing the battery will be full next time you need to mow the lawn.

Tractor Supply Co. is your one-stop-shop for all your lawn maintenance needs. Browse our variety of lawn mower attachments, accessories, and outdoor power tools. We can also help you pick the lawn mower that's right for you and share the top tricks on how to grow a beautiful and thriving lawn.