How Long to Charge a Lawn Mower Battery [Tips-&-Tricks]

By | May 26, 2023

YardSimply is supported by readers like you. We may earn an affiliate commission if you purchase through links on our site. Learn why you can trust us here.

It’s always annoying when you go to mow the lawn and your battery is dead. Or, even worse, when it dies halfway through and you have to recharge it.

So how long to charge a lawn mower battery?

How Long To Charge a Lawn Mower Battery On A Trickle Charge?

How long does it take to charge a lawn mower battery? The answer may surprise you – it depends on the size of your battery and the type of charger you are using.

Slow chargers, also known as Trickle Chargers, can take up to 24 hours to fully charge a single 12-volt Lawn Mower Battery.

Fast chargers will do the job in half that time or less. It is important to select the right charger for your needs because overcharging a lead acid battery will shorten its life.

Most home improvement stores sell both types of chargers; some even have models specifically designed for automotive batteries. You can also find them online from various retailers including

 If this is your first time charging a lawn mower battery, we recommend starting with a slow charger until you get familiar with the process

The Charger You Use Matters

If you own a quiet lawn mower, then you know that one of the most important parts of keeping it running smoothly is to make sure the battery is always charged.

But how do you know how long to charge a lawn mower battery? Well, it depends on the charger you use.


The voltage of your charging system should match the voltage of your lawn mower battery.

Most standard batteries are 12 volts, so if your charger is also 12 volts, then charging will be simple and straightforward.

If not, then you may need an adapter in order to connect them properly. 


The amperage rating on your charger should be at least as high as the number printed on your lawn mower battery.

This number represents how much current (in amps)the charger can provide safely without damaging either itself or the battery where from 50-75% (of maximum capacity).

Anything below this risks overcharging which could damage or shorten lifespan significantly! 

Useful Features:  

Some features available with certain chargers can include things like automatic shut off once full power has been reached to prevent overcharging, digital displays showing progress/status, built-in temperature sensors for safety.

These often come at slightly higher price points but offer greater convenience & peace of mind.

How Can You Charge A Lawn Mower Battery Properly?

It is always important to follow basic safety guidelines when handling or working with batteries. This includes understanding how to properly charge a lawn mower battery. 

The first step is to locate the battery. Once you have found the battery, connect the positive and negative charging cables. 

The next step is to allow the battery to charge for an appropriate amount of time before disconnecting the charger. 

Finally, once you have finished charging the lawn mower battery, be sure to disconnect the cables in the reverse order that you connected them.

Factors that Impact How Long It Takes to Charge a Lawn Mower Battery

It is common for people to wonder how long it takes to charge a lawn mower battery. After all, if you are like most people, you probably do not use your lawn mower that often. As a result, the battery may not get used very often either.

When you do need to use it, though, you want to make sure that the battery is fully charged so that your lawn mower will start up and run properly.

So, how long does it take to charge a lawn mower battery? The answer depends on several factors, including the type of battery, the voltage of the charger, and the amp-hour rating of the charger.

The type of battery impacts how long it takes to charge because there are different types of batteries with different chemistries. The most common types of batteries used in lawn mowers are lead-acid batteries.

These batteries typically take about eight hours to charge fully from an electric outlet. If you are using a gas-powered generator to charge your lead-acid battery, it will take longer – usually around 12 hours or more.

The voltage of your charger also affects how long it takes to charge your lawn mower battery.

Most chargers have either 6 or 12 volts output – with 12 volts being more powerful. A higher voltage charger will charge your battery faster than a lower voltage one.

For example, if you have a 12 volt charger and a lead-acid battery, it will take about four hours to charge the Battery completely from empty.

If you have a 6 volt charger instead, it would take twice as long – eight hours – to achieve the same full charge on your lead-acid Battery.

Finally, the amp hour rating on your charger also has an impact on charging times for your lawn mower Battery.

This rating tells you how much current – measured in amperes – can flow from the charger in one hour without damaging the Battery.

A higher amp hour rating means that more current can flow in a shorter period of time; thus resulting in a faster charge time for your Battery.

For example, if you had two identical chargers but one was rated at 2 amps and the other was rated at 4 amps, then the latter would be able to provide twice as much current and could potentially charge your Battery in half of the time as the former charger  (all else being equal ).

In general, then, you can expect a lead acid battery to partially charge in about four hours when connected to the grid via an electrical outlet and using a 12 volt 2 amp charger.

However, “fast” charging of lead acid batteries is not recommended by manufacturers and also may decrease the battery’s service life

Why you should trust us

There are a lot of different lawn mowers on the market, and it can be tough to know which one is right for you. 

Senior staff writer Zane Williams has done the homework and spent over 100 hours researching different types of mowers and talking to experts in the field like Justin Watkins of Earth Tones Landscaping

And we’ve put together this guide to help you make an informed decision about which one is right for you.

We only recommend products that we believe in and that we think will deliver value for money. 

We also test each of the mowers ourselves before giving our final verdict – so you can rest assured that they meet our high standards. 

Our goal is to help you find a lawn mower that suits your needs, budget, and lifestyle so that you can enjoy your backyard space worry-free.

FAQs About Length of Time to Charge Lawn Mower Batteries

How Long to Charge a Lawn Mower’s Battery at 6 Amps?

It would take approximately 2 hours to charge a lawn mower’s battery at 6 amps.

How Long to Charge a Lawn Mower’s Battery at 10 Amps?

It would take approximately 1 hour to charge a lawn mower’s battery at 10 amps.

How Long to Charge a Lawn Mower’s Battery at 40 Amps?

To charge a Lawn Mower’s Battery at 40 Amps will take approximately 5 minutes for a 6 volt charger, and approximately 50 minutes with a 12 volt charger.

How Long to Charge a Lawn Mower Batteries with a Trickle Charger?

If you are using a trickle charger to charge your lawn mower batteries, it will take approximately 24 hours to fully charge the battery.