Lawn mower battery struggles

[jes_in_sac]

I got tired of the worthless Lawn and Garden lead acid batteries. I've been using ATV/Motorcycle AGM sealed batteries, and they are much more durable, particularly on the rough acreage I run my mower over. And they are cheaper online, with no core charges. For the same amps, they will usually be a little smaller, so I just fill the gap with some foam packing material, which even further cushions them. And yes, definitely keep a battery tender on it... summer and winter. All of my batteries on the farm have a battery maintainer on them. You can even buy them in multiples for cheap online. I have a solar powered one on my dump trailer. Batteries have gotten expensive, and most of them "lightened up" [less lead], so it helps to keep them maintained to last as long as possible and a maintainer helps keep them from sulfation [clogging up internally] when they just sit there.

 

[Ken_L]

A couple years ago I bought a NOCO Genius1 charger described as an "automatic maintainer, trickle charger & desulfator with overcharge protection & temperature compensation for lead acid & lithium batteries." It's like a $30 item. I'm an electrical engineer and I don't know enough about batteries to understand what this thing does or exactly how to use it. Based on my bad luck with batteries, over the winter I disconnect my battery, store it in my basement and connect this charger a few times for a couple days. During the mowing season I'll use it periodically. It's too early to tell whether it will pay off but just this week I reconnected the battery to the mower after first installing this battery disconnect switch to the negative terminal. I wonder if the charger and disconnect switch would allow me to leave the battery in the mower over the winter since removing my battery is a royal pain because I have to move a hydraulic fluid tank out of the way to get to the battery.

You can leave an automatic maintainer on the installed battery all winter. I have used one on our Corvette for over 11 years on the same battery. I think they really make batteries last longer.

 

[Raymo69]

Listen to all the above advise - its good.
I have never heard of a "battery tender" - do you mean trickle charger?
I have no less than four battery chargers (diffrent amp's). All of them go to trickle/standby charge, once the battery gets fully toped up.
I never leave my batteries on charge for more than 48 hrs - usually just overnight.
I get cranky if a battery only lasts 5 years - my best to date was 9 years.

Battery Tender is a name brand of a trickle charger, probably the most popular one out there. I have 6 batteries in 6 different vehicles plugged in year round with Battery Tenders & get 8-10 years out of my batteries.

 

[Rebel1]

I was just wondering how many of the people on this forum dont do anything with their lawn mower battery when storing it for the season. I dont put a tender on mine. All I do is unhook the negative cable and leave battery in the mower till spring and then I just hook cable back up and start it. I can usually do this for 4 years with no problems and on the 5th year I have to jump or charge it or get a new battery. Also if I do have a dead battery come spring, what amp do most people use to charge up a rider mower battery?

If you are getting 4 years out of a battery that is probably better that most people are getting so no matter what you do it’s not going to increase the battery life over 4 to 5 years. I use a Harbor Freight $7 float charger on my generator and portable air compressor and have for years, they won’t charge a dead battery but just keeps a healthy battery fully charged. My Toro Z-master 5000 mower is in a shed that doesn’t have power so I bought a 12V solar charger from Academy about 10 years ago for around $20 and it still works great. The best battery I have found is Lowes Magna Pro, I just changed it out a few weeks ago it was 5 years old.

 

[tbzep]

I was just wondering how many of the people on this forum dont do anything with their lawn mower battery when storing it for the season. I dont put a tender on mine. All I do is unhook the negative cable and leave battery in the mower till spring and then I just hook cable back up and start it. I can usually do this for 4 years with no problems and on the 5th year I have to jump or charge it or get a new battery. Also if I do have a dead battery come spring, what amp do most people use to charge up a rider mower battery?

I bought my current Gravely ZTHD in the spring of 2017. The battery lasted through a few cuts last year, so that's about 8 years. I use a Battery Tender Jr. between it and my ATV, swapping it every couple of weeks over the winter, no special schedule, just whenever I think about it. The tender only charges for a couple minutes at most before showing green. When we expect single digit lows, I make sure they both are charged and swap the tender every few days. I don't use the tender in the summer.

For what it is worth, I just replaced one of my motorcycle batteries a couple weeks ago. The OEM was a YUASA AGM, which didn't last all that long. I put a MotoBatt AGM manufactured on 12/4/16 on it and the offbrand sucker lasted 9 years and 3 months. I keep tenders on both of my bikes year round because I may ride one several days in a row and then not ride it again for a month.

 

[Auto Doc's]

Hello S,

You are being frugal on batteries and that is understandable with the rip off prices, but there will come a time where a battery will fail internally, and jumpstarting will no longer work. When that happens the charging system components will burn themself out and bigger problems happen that will make the mower totally unusable.

Most of my riders sit outside covered, but I use solar panel battery maintainers and they work exceptionally well. I just keep them connected year-round and I have strong batteries.

It only takes a few milliamps to keep a battery active so it will not destroy itself from sulfation deposits forming.

I make a point of firing up all of my battery start equipment at the first of the month regardless, so they get a good exercise run. This also keep the fuel from stagnating in the carburetors and creating running problems

 

[northcreeek262]

Listen to all the above advise - its good.
I have never heard of a "battery tender" - do you mean trickle charger?
I have no less than four battery chargers (diffrent amp's). All of them go to trickle/standby charge, once the battery gets fully toped up.
I never leave my batteries on charge for more than 48 hrs - usually just overnight.
I get cranky if a battery only lasts 5 years - my best to date was 9 years.

Unlike a trickle charger a maintainer only gives the battery what it needs not just a low amp constant. Some are free standing and some are onboard types, I use both types depending on application. I use Schumacher and have had good luck with them, my batteries have been lasting amazingly long and they are always ready to go.

 

[jviews12]

bring into warm garage, charge 3 times during winter and before fit=rst use in spring. 5 years for this type of battery is a god send with bad maintenance and freezing in winter.

 

[rhkraft]

Cold is tough on lead acid batteries. Should the battery discharge, it can freeze and crack the case. If you live in a cold climate remove the battery and store in a heated space. Charge it overnight maybe twice over the winter and top off before you install it. A fully charged battery is easier on the charging system Check the acid level before the spring charge unless it is sealed. Remove any corrosion before installing and spray with battery post protectant. Should get 5-7 years out of it. On a side note, when you buy any new battery that has fillable cells, check the level when it is new. If the cells are down, fill with acid, not water, to establish 1.265 specific gravity for full performance. After that, only add distilled water. Too many battery stores fill their batteries with acid to the fill line, but the plates soak some up and almost all are low on acid when you buy them. Properly prepared auto batteries can last 6-8 years. We do this with new aircraft batteries to maintain performance. If you own a single engine airplane or have access, used aircraft batteries fit in riding mowers. Since they design to crank 150 -180 HP aircraft engines, when they get too weak for the plane, there is lots of power left for your 20HP mower. I used old aircraft batteries all the time, never bought a new lawn mower battery. Go out to the airport, they might give them to you, just check the water and charge.

 

[Smithsonite]

Not to pee on anyone's fire, but my experience has shown the exact opposite. Warmer temperatures cause batteries of any kind to self-discharge at a higher rate. Makes sense, since when you try and start your car at zero degrees, it cranks slower - not just because of thick engine oil, but the chemical reactions in the battery slow as well.

A colder battery self-discharges MUCH slower. That's the exact reason that up here in MA I get 8-13 years out of lead acid batteries, but when I lived in Phoenix, AZ, 3 years was doing really good. So, leaving my batteries in the machines or vehicles out in the non-climate controlled garage makes most of them last over 12 years most of the time. (EDIT to clarify the small engine / Z-turn mower batteries aren't as robust as automotive batteries, so I get 5-8 years out of those.)

Caveat to that is my vehicles are all 30+ years old. You won't get that life out of any battery in a modern vehicle. There's too many modules constantly pulling power. GM products run EVAP tests while you're in the house sleeping! They've been doing that at least since the 2007 model year, maybe even prior. It's crazy these days ...



I've owned BatteryMINDer multi-stage, temperature-sensing chargers since 2016. The amount of batteries these chargers have saved me has paid for all 4 of them over and over again.

I never disconnect cables. There's no need to, unless it's computer controlled, like every modern vehicle today. Park one of those any longer than 2 weeks and you'll be out of luck trying to GET IN the damned thing with the key fob ... never mind starting it, lol. Glad my newest car is now a 1994 model. Sanity returned!!

Anyway ... having been in small engine and auto repair most of my adult life, I'll tell you that I've experimented with every new and fancy type of battery out there from AGM to lithium iron phosphate. What I've found is I always come right back to the tried and true lead acid. For one thing, none of these charging systems was designed to maintain anything other than a lead acid battery (except for modern start-stop vehicles). Even with help from my top-of-the-line battery charger, I've never had an AGM make it past 5 years. On that note, I just pulled a regular lead-acid battery from one of my 30 year old Volvos, only as a troubleshooting step. Since it was 11-1/2 years old, I left it out & kept the 8 year old one in there instead. I didn't even need to change it - was still starting the car no problem.

I've had many AGMs fail much sooner than regular lead acid ones did, both in automotive and small engine duty. The $300 Odyssey AGM I had in my Silverado barely made it 5 years with EXTENSIVE help of my charger!

The only alternative battery I use these days is a sealed lead acid (SLA) alarm system battery in my 1974 Yamaha RD350 2-stroke motorcycle that's still running dual points ignition. I've found you can abuse the heck out of those by neglecting them for months, running them way down, and I'll still get 5-6 years out of them at just $25 a pop. Can't beat that!