Replacing battery in lawn mower

When minor issues pile up, it may be a sign it's time to replace your lawn mower altogether. However, before you start shopping for the latest model and finding the perfect mower for your grass type, it's worthwhile to see if your lawn mower's problems are instead the result of a battery in need of replacement.

Batteries wear down over time with regular use, even when you take the time for proper maintenance. In fact, at best, lawn mower batteries last three to five years. As they degrade, you'll notice a few symptoms that indicate your battery is failing. For example, if your mower's battery won't hold a charge even after time on the charger, this may be a sign that the problem isn't necessarily with your lawn mower but the battery itself. It means the internal cells are starting to degrade, which is natural. Keeping an eye out not just for difficulties keeping a charge but the two signs below can help you catch problems sooner and may encourage you to replace the battery before it's completely dead — saving you the hassle of running to the hardware store mid-mow. It can also help you maintain your overall lawn mower and reduce the likelihood of damage as a result of a failing battery.

If you're unsure about this process, it's best to speak with a lawn mower professional to learn the right steps and properly diagnose your mower's problem. You can also consult your owner's manual for specific information.

You're Having Difficulties Starting Your Lawn Mower

Person trying to figure out what's wrong with the lawn mower

You walk outside, ready to tackle the task of mowing your lawn, and go to start your lawn mower, only to find that it struggles to start — or that it won't start at all. This isn't just a frustrating inconvenience: it's also a sign your lawn mower battery is on its last legs.

However, there are a few other reasons that your battery might not be started, which should be ruled out first. This is especially true if your battery hasn't yet reached the end of its lifespan, when deterioration is more common. If your mower clicks or otherwise sounds like it's struggling to turn over, it could be something besides your battery. For mowers that start but struggle to do so, it could be a bad starter. Differentiating between the problems could require the guidance of a professional. If the mower never starts at all and you know the battery's still good, you may want to start looking for a replacement.

Your Lawn Mower Battery Has Visible Damage

Person looking at lawn mower battery

If you're not regularly using your lawn mower, you may not notice the above signs. This is especially true for starting issues, which you'll only notice when you turn your lawn mower on. However, there is an additional sign that it's time to replace your lawn mower's battery that you can look for without ever turning your mower on or trying to charge the battery.

Look for visible damage when assessing your lawn mower battery's health, particularly at the contacts. Damage can occur as a result of normal wear and tear or improper storage. Batteries exposed to extreme heat or cold for a long time will wear down faster. There's no single appearance for damage — instead, swelling, corrosion, cracking, and leaking are all signs that your battery is damaged and in need of a replacement.

If you notice any signs of damage on your battery, a quick replacement can help avoid unfavorable outcomes, like your battery failing to start when you do turn it on. While damage may occur naturally as your battery reaches the end of its lifespan or with regular, frequent use, you can reduce the likelihood of damage by storing your lawn mower battery properly. When you're done mowing, remove the battery from your mower and keep it in a safe, secure location with no extreme temperatures or heavy sun exposure. Finally, the best thing you can do while a battery is in long-term storage is to fully charge it first, then connect it to a trickle charger or smart charger.