Choose The Correct Charger For Your Lawn Mower's Battery With These Tips

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Most people realize they have to perform regular maintenance to extend the life of a lawn mower. Most also understand that if they don't routinely fill their mower with gas, it won't go. But, what many fail to foresee is the need to regularly charge the battery on their gas-powered lawn mower. This typically isn't an issue on push or self-propelled models, unless it has an electric start. If you have determined a riding lawn mower or lawn tractor is best for your lawn, however, the battery that will need to be charged. Ditto for a zero turn. Regardless of model, you will need a battery charger to perform this task. In order to choose the correct charger for your lawn mower's battery, you should consider the frequency of use and typical run time of your mower. Most importantly, you should choose a charger that delivers the correct voltage and amperage.

When you begin looking at chargers, the first thing to consider is voltage. Lawn mower batteries will be either 6 or 12 volts. You need to match the battery voltage with the charger, or the charger will be too weak or powerful. That means you either will not be able to fully charge your battery or you could very likely damage the battery and/or electrical components on your mower. You also need to check that the charger is meant for the type of battery you are charging, i.e. lead-acid. While the voltage is the maximum of pressure or current that a battery can hold, amperage is the rate at which the electrical current flows. So, what you are looking for when choosing a charger is the level of charge the device is capable of producing and how fast it delivers it.

Batteries lose power both by being used and not being used. This means they will require charging whether you are using them or not. To that end, most larger riding and zero turn mowers have an alternator to charge the battery while the mower is in use, just as your automobile does. However, the mower often isn't running long enough to provide an adequate charge to keep the battery level full. Additionally, the battery is also draining during the extended sit time between mowing sessions. Hence the need for a charger and the need to consider the frequency of use and typical run time of your mower.

Mowers that are used frequently or for extended periods of time typically just need a bit of charge to maintain the battery level between uses. This is because the mower either doesn't sit long enough to result in a huge power drain or runs long enough during usage to adequately charge the battery. In this situation, a slow charger, often referred to as a trickle charger, is a good choice, particularly during winter storage. It provides a low amperage charge over a long period of time. This is considered the safest method of charging and is also the best for prolonging the life of your battery, as the slow delivery of electrical charge prevents an excessive amount of heat building up. 

While trickle chargers are the safest, they are also the slowest. Therefore, if the battery level is very low, they will not provide current flow fast enough to adequately charge. This often happens on mowers without alternators. In this instance, it's necessary to utilize a charger that delivers more amps. However, on smaller lawn mower batteries, it is advisable not to exceed 10 amps during charging.

Just as there are crucial features to look for when buying a new lawn mower, there is a myriad of qualities to consider when buying a battery charger. The most basic types, such as the Orion Motor Tech 12V trickle charger and battery maintainer, deliver a steady of amount of amps all the time, have no settings or features to deviate from that, and must be manually plugged in or unplugged to start or stop the charge. Working up from there are options such as automatic shutoff, which can prevent overcharging and is a nice safety feature to have. Many also have timers or failsafes that prevent charging if the charger is hooked up wrong. Float mode, which even most basic trickle chargers incorporate, is meant to maintain the battery at a full charge without overcharging.

Many more advanced models, such as the Craftsman 4-in-1 battery charger, tester, and maintainer, are fully automatic and allow you to change between various voltage levels and amperage rates. In essence, these multifunctional chargers can be used either as a trickle charger or a fast charger, depending on the situation. They can also be used to charge various battery sizes and types. This is particularly handy if you have multiple batteries you need to regularly charge, such as those on your lawn mower, boat, motorcycle, or car. Some models can even test battery levels. Others offer a jump start option in the event your lawn mower battery is completely dead and you need to get it going immediately.