You set up your robotic lawn mower and go off to hang out with your family. After all, you want to live your life rather than spending your weekends cutting the grass. That is the whole point of having a robot mower!  After only 25 minutes, you notice your Tony Stark (yes, in our story, you gave the autonomous mower a nickname) heading back to the charging station. Tony used to be able to mow for an hour between charges. What’s up with your robotic mower battery life being so short?

The truth is that there are several different reasons why your robot mower’s battery life might be shorter than you expect. Like Scooby Doo, we are here to help you solve the mystery. Below, we have listed the 5 main reasons why you might be experiencing a short charge on your robotic lawn mower. We have listed them in order of the most common to the least common.  

But first, we start with a few basics about robotic mower battery life.

Robot Mower Battery Life Fundamentals

We need to begin by defining how you know if your robot mower’s battery performance is problematic. Some people think that if the mower can’t complete the whole lawn in a single charge, it’s a problem. Not necessarily.

Many homeowners with robotic mowers find that their mowers need to recharge partway through the lawn. This is perfectly normal. Most machines are not designed to cover entire properties in one go.

Plus, other factors external to the machine can influence how much ground it covers in a charge. For example, if the grass is particularly high or thick or wet, the electric robotic lawn mower will need more charges than usual. 

Similarly, temperature can impact a robotic mower. As much as possible, you want to keep the mower out of harsh direct sunlight. (Obviously, you can’t always help this when the mower is cutting, but you can while it is docked. We recommend putting the dock under shade or keeping the robotic mower in its own garage.) Cooler temperatures also impact the battery life of a robot mower.

So if your mower goes back to charge after an hour of work, that’s not necessarily a cause for alarm. However, if you are noticing that the battery life is quite a bit lower than it was previously, even in similar conditions, you want to investigate. Or, if the mower can no longer properly maintain the yard, you want to investigate. Finally, if the robotic mower is not meeting its rated capacity… (bet you know where this is going) …you want to investigate.

Without further ado, here are a few potential causes of short robotic mower battery life that you may discover, Columbo.

1. The mower’s settings are wrong.

As we promised above, we are starting with the most common cause of diminished battery in a robot mower. And happily, this is the easiest one to fix. 

If you do not have your robotic mower running with the ideal settings, it can cause the battery to drain quickly.  For example, if the find wire settings are too high, the mower may be expending too much energy on that than on the mowing itself. If the cutting schedule is too aggressive, the mower may be working too hard.

Again, this problem has the easiest fix. Simply adjust the settings, and you are good to go!

2. The mower is not the right fit for the space.

Different robotic mowers are made for different kinds of spaces. Smaller models are made for smaller lawns. If you try to use one on an expansive property, it will not have the power to cut on the consistent schedule you need for the yard to look nice.

Another factor is the slope of the lawn. We ran an extensive test of robotic mowers on hills to show that some are better suited than others.  Even if a Gardena Minimo can make it up a hill okay, it needs a lot of battery power to do so because it wasn’t made for that task.  The Mammotion Luba, on the other hand, can handle a hilly yard much more easily without draining the battery.

For this reason, we cannot stress enough how important it is to choose the right robotic mower for your lawn. Doing so will help reduce robotic mower battery issues. Before you make the investment, be sure to reach out to robotic lawn mower experts to help you find the right option for your space. The wrong mower can, unfortunately, be a costly mistake. 

3. The charging system isn’t working properly.

Remember the classic old-school Nintendo console? You would put in the cartridge to go rescue Princess from the grasp of the evil Bowser. However, all you would get on the screen was some random white and pink boxes. What did you do? (And yes, we realize that those of you under the age of 30 will never know this joy.)  You took out the cartridge, blew out the dust, and then tried again.

Why did we do this? Inside the cartridge and inside the console was some metal circuitry. When you cleaned it out, the metal fit together properly again. Then, the machines would be able to clearly communicate again.

Robotic lawn mowers work similarly. When they go back to their charging station, metal sensors on the mower attach to sensors on the charger. (Here is a great primer on how robotic mowers charge.) So, if you are experiencing robotic mower battery issues, it could be an issue with the charger, not the mower.

Start by making sure no debris is interfering with the docking process. Then clean the charging surface using a damp cloth (preferably a fine grade emery cloth). If necessary, you can use a mild soap solution or even some fine sandpaper if you notice corrosion.  Just be sure to not use harsh chemicals or do any power washing. Also, be sure the charger is unplugged when you clean it.

If cleaning the contacts doesn’t work, but you still suspect that the problem lies with the charging station, you might need a new charger. They generally run between $50-$200. So it’s a cheaper solution than a new mower—and often cheaper than a new battery.

4. Your battery is old. 

If you ever talk to someone over 40, be prepared to hear a diatribe about how much their body has started hurting and creaking since they reached that magical age.

Well, in that sense, a robotic lawn mower battery and a human are somewhat similar. A robotic mower’s battery life also diminishes as it ages.

The typical robotic mower battery lifespan is 3-5 years.  So if your mower is more than 3 years old, and you are noticing shorter mowing times or reduced mowing power, you may need to replace the battery.  

Again, luckily, this is an easier and less expensive solution than some of the others on our list. Buy a new battery for the robotic lawn mower and replace it. (If you need help doing this, contact Autmow, and we would be happy to help.)

5. The battery or the mower is damaged.

OK, we have reached the least common reason for robotic mower battery issues.  However, this one is also the most serious.

On very rare occasion, a robotic mower battery (or the mower itself) becomes damaged. Why does this happen? Usually it is because the battery was dropped or pierced. Damage can also occur if the battery has been exposed to extreme temperatures or been pushed to the limits of its capacity too many times.  

If your battery or your mower has been damaged, the most common signs are that the mower will not start or that it will turn off unexpectedly. In very rare cases, you might notice the battery leaking, in which case you want to contact robotic mowing experts immediately. In even rarer cases, you might notice the battery smoking. If you ever see that, call the fire department immediately.

While this cause of a shorter robotic mower battery life is potentially the most serious, the good news is that it is far less common than any other cause on our list.  And once you have dealt with the damaged parts, you simply need to replace them.

Robotic mower battery issue solved

All right, detectives. By this point, we should have successfully solved another case. By going through these 5 common reasons for a shorter robotic mower battery life, you have hopefully found the one impacting you.  If not, contact Autmow, and we can help you troubleshoot even further.

Proper robot mower maintenance for improved battery life

Honestly, as much as we all love solving mysteries, let’s be honest: you don’t want to be dealing with robotic mower battery issues often.  Thankfully, with a few small steps, you should have very little trouble with your battery. 

Here are steps you can take to ensure your robotic mower battery life stays at its peak for as long as possible:

  • Keep your autonomous mower on a regular schedule.
  • As possible, avoid direct sun and freezing temps.
  • Use settings such as eco modes or charge cycles to conserve energy.
  • (Most importantly!) Make sure you have the mower that is the right fit for your lawn.

(You can read more great robotic mower maintenance tips here.)

Following these tips will keep your robotic mower battery happy for a long time.  And as the old adage goes, “If the robotic mower battery ain’t happy, nobody happy.”