How to Charge a Lawn Mower Battery?
A lawn mower uses a battery to start the engine, supplies power to the clutch, and powers other components like the headlights. Mowers have convertors in them to charge the battery from the engine’s power but over time the charge runs out. Battery can also drain if you do not use the mower for a long time or because of weather conditions. You will need to charge the battery regularly or else the machine will not start and function well.
There are various methods of charging a mower battery such as with a charger, with solar power, hand-crank generator or with a portable gasoline generator.
Most riding lawn mowers use a 12 volt battery while some smaller ones use a 6 volt battery. The voltage will be written on the battery and in the instruction manual for the mower. You should use a charger with 10 amps or lower while charging the battery.
Charging With a Charger
The easiest method of charging the mower battery is with a charger. This equipment allows you to charge your mower battery using your house’s or garage’s power outlet. Always follow safety precautions while charging the battery. Use safety gloves and goggles and wear protective clothings like a full sleeved shirt.
A typical 12 volt battery charger will cost $20-$80 while more expensive chargers will cost $150-$250.
Gather the Necessary Tools and Materials
Listed below are the necessary tools for charging your mower battery.
- Suitable sized wrench.
- Screwdriver.
- Charger.
- Charging cable
- Protective gloves
- Small container to store nuts and bolts
Prepare the Battery and Surroundings
Find the location of the battery in your mower. Most riding mowers usually have their battery under the seat while some manufacturers put it next to the engine.
Make sure that the machine is turned off and no electrical parts are taking power from the battery such as the headlights or the backlights.
Remove hard metal wires or plates that are keeping the battery in place and take out all the screws that are connected to the electrical wires. Keep the screws in a secured place to avoid losing them.
Make sure that none of the wires that take power from the battery to other parts of the mower are connected.
Connect the Charger
Disconnect your charger from the power outlet. Take out your charger and connect the cables to the battery. There are two cables of the charger where the red cable is for positive connection and the black cable is for negative connection.
Always start with connecting the positive side first. Connect the red cable to the positive connecting point of the battery and then connect the black cable to the negative terminal connecting point of the battery.
Set the Charger
Chargers usually have multiple voltage settings on them. Match the charger voltage to the voltage of your battery. Usually the batteries are 12 volt and all chargers have a 12 volt setting. Make sure to lower the settings to 6 volt if your battery is of that voltage. Do not mismatch the voltage as it will affect the charging process and decrease the longevity of your battery.
Ensure that the charger’s amps are in the correct settings. Most batteries are charged with 10 amps or lower chargers. Avoid using higher amps as it might cause damage to the battery.
Connect the charger to your house or garage’s power outlet after making sure that all the correct cables are connected to the right terminal and the right settings are in place. Turn on the power and start the charging process.
Charging Process
The battery will start to charge as soon as you turn on the power of the electrical outlet. The charger will indicate that the charging process has started and that the battery is charging.
A 12 volt battery at 10 amps should take somewhere between 2 to 7 hours to fully charge depending on how much charge is left in the battery. You can charge it slower at lower amps which can take up to 12 hours.
Do not interrupt the charging process and let the battery charge fully. The charger will indicate that the battery has gotten full charge when the charging process is complete.
You can partially charge the battery if you are in a hurry. Your mower will start and function without full charge.
Disconnect the Charger
Turn off the power outlet when the charger indicates that the charging process is complete. Remove the negative black cable first and then remove the positive red cable. Do not overcharge the battery.
Allow the Battery to Rest
Charging the battery fully will cause it to heat up. You should not start the mower as soon as charging is completed. Keep the battery at rest for at least 8 hours before usage.
Reinstall the battery
Reinstall the battery in place with the screws that you took off earlier. Correctly reattach the hard metal wires or plates that securely keep the battery in place.
Charging Without a Charger
You might get into situations where you do not have a power outlet near your mower or your house runs out of electricity. In these situations, you can use jumper cables, a hand-crank charger or a solar powered charger to power your battery.
Jump-Starting With a Vehicle
Jump-starting the mower with another vehicle like a car is useful if you are in a hurry to mow your lawn and want to charge the battery afterwards. Follow these steps to jump-start your mower.
- Park the car and the mower next to each other and make sure that they are not touching each other.
- Turn off the engine of your car and your mower. Never connect the batteries while your engine is running.
- Lift up the hood of your car and lift up the seat of your mower to access both vehicle’s batteries.
- Take a jumper cable and clamp the red positive cable to the positive terminal of your car battery.
- Take the other end of the red positive cable and clamp it to the positive terminal of your mower.
- Then connect the black negative cable to the negative terminal of your car battery. Connect the other point of the black jumper cable to the metal body of your tractor. Make sure that this point is sufficiently away from the fuel tank, the engine, and other electrical parts.
- Turn on the ignition of your mower to supply power from the car’s battery to your mower battery.
- Remove the cables in the opposite order of installation. Remove the black cable first from the mower and from the car’s battery and then remove the red cable from the mower and then from the car’s battery.
- Charge the mower battery after your mowing activities are completed.
You can buy a jumper cable for $10-$50.
Hand-Crank Chargers
Hand-crank charger is also a good temporary solution for charging your mower battery. Hand-crank chargers convert the cranking motion to electricity. Make sure to match the output voltage of your hand-crank generator to the voltage of your battery.
Connect the hand-crank charger’s red positive connection to the positive terminal of your battery and then connect the black negative connection to the negative terminal. Start cranking when all the connections are in place.
Hand crank generators put out 2-3 amps of electricity so it will take quite a long time to fully charge the battery. You can operate the vehicle after partial charging. A hand-crank charger will cost you $100-$250.
Solar-Powered Chargers
A solar-powered charger converts sunlight to electricity that can charge your mower battery. Use the clamp cable extensions with your solar-powered chargers to charge your mower battery. Connect the red positive cable to the positive terminal and the black negative cable to the negative terminal. The battery should automatically charge.
A 12 volt and 10 amps with lower amps settings solar-powered charger will cost $25-$35.
Lawn Mower Alternative Charging Methods
You can use other charging methods like trickle charging or using a portable generator to charge your mower battery. Trickle charging ensures longevity of your battery. You can also easily swap your battery with a newer one if it completely dies.
Using a Portable Generator
You can use a portable generator to charge your car battery. Portable generators convert gasoline’s chemical energy to electrical energy. Generators supply AC(Alternating Current) that cannot be directly supplied to your battery. You will need a regular charger to convert the AC to DC(Direct Current). Make sure that the portable generator’s output AC matches with your charger’s required AC.
Connect the charger to your battery and then connect the charger’s input cable to your portable generator. Wait for the charging to be completed and then turn off the generator and disconnect all the cables.
Keep the generator in a cool, dry, and well ventilated space so that the heat and smoke can disperse properly. Do not touch the generator while it is running to avoid accidental burns on your skin.
A 2 kilowatt to 5 kilowatt hour portable generator will cost you somewhere between $300 to $1500.
Trickle Charging
Trickle chargers use very low amps like 1-3 amps to charge the battery over a long period of time. Trickle charging not only ensures that the battery is not overcharged but also the low amps assure that your battery is charged safely without any overheating issue.
Keep in mind that trickle charging takes way longer than regular charging as it charges the battery with very low amps. It can take days depending on the charge level of your battery.
Trickle charging method is similar to using a regular charger. Disconnect all the wirings of your mower battery and connect the trickle charger’s positive red cable to the positive terminal of your battery and connect the negative terminal to the negative black cable. Connect the charger to your power outlet and begin charging.
Check after a few hours to see if the battery is charging properly. Turn off and disconnect the cable from the power outlet after the charging process is completed. Remove the negative black wire first and then remove the positive black wire.
A trickle charger will cost you $20-$100.
Battery Swapping
You can easily swap the battery of your mower if it is completely dead or you are in a hurry and have a spare fully charged battery lying around. The steps of swapping the battery are given below.
- Locate your mower battery: Most riding mowers install the battery under the seat while some mowers install it next to the engine. Check the instruction manual if you cannot find it.
- Make sure that your mower is turned off and no component is using the battery power.
- Gather the necessary tools for disassembly: Find the suitable wrench that matches the size of the screws that are connecting the mower cables with the battery and the screws that are holding the battery in place.
- Follow safety precautions: Use protective gloves and clothes while handling the electrical wires.
- Remove the screws and the metal plates or wires that are keeping the battery connected to the mower. Remove the black negative connection first and then the red positive connection.
- Store all the screws, wires, and clips in a secure place to avoid losing them.
- Take out the battery and lower it gently on the surface.
- Put the new battery keeping in mind the position of the older battery.
- Screw all the connections back. Remember to put the positive red connection first and negative black connection second.
- Put back the hard metal wires or plates that keep the battery from moving around.
- Start the mower to see if the connections are in the right place and the mower is getting power from the battery.
How Long Does It Take to Charge a Lawn Mower Battery
Depending on the amps of your charger and the resistance of the cables of your charger it can take 4 hours to days to completely charge your mower battery.
How Long to Charge Lawn Mower Battery 2 Amps
It takes approximately 24 hours to charge a mower battery with a 2 amps charger. Using a low amp charger like a 2 amps charger will keep your battery from overcharging and overheating but it will take longer.
How Long to Charge Lawn Mower Battery at 10 Amps
It will take approximately 4.5 hours to completely charge your 12 volt battery with a 10 amps charger. This type of charger is the most common and the most recommended while charging a 12 volt battery.
How Long to Charge a Lawn Mower Battery at 40 Amps
It will take approximately 1.2 hours to completely charge your 12 volt battery with a 40 amps charger. This type of charger is not recommended for this type of battery. Make sure to check frequently to make sure your battery is not overcharging or overheating if you do choose a 40 amps charger.
How Much Does It Cost to Charge a Lawn Mower Battery
The cost of fully charging a lawn mower battery depends on three factors such as, the voltage of the battery, Amps hour of the battery and kilowatt hour rate of electricity of your house or garage. Multiply the amps hour and voltage of your battery and divide by a thousand.
For example, if your battery is 12 volt and 100 amps hour, then the figure stands at =(12*100)/1000=1.2 kilowatt hour. Now multiply this figure with your kilowatt hour rate of electricity. The average rate in the USA is $0.23 for every kilowatt hour. So in one hour it will cost you (1.2*.23) =$0.276 or roughly 3 cents. If it takes approximately 4 hours to charge, it will cost you 12 cents to charge your battery.
So, make sure to regularly check and maintain your mower battery before every usage to ensure proper function of your mower. A drained battery will hamper the start of the engine and cause other components like the clutch or the headlights to function poorly. Check the charger and all the connections regularly to ensure proper charging of your battery. Stop charging if the battery or the charger overheats.
