Ryobi battery riding lawn mower

[JeremyA]

Just got an RM480ex - been breaking it in slowly (4 mows so far, depleting 3 bars each time). I am only getting 15-20 minutes run time doing this - is this to be expected? I called the Ryobi help line and they told me that it is normal and that I should only be expecting 1 hour or so in run time considering terrain and grass length (the year is fairly flat and the grass is not very long) but that seems to be counter to what I have seen here an other places online. They also told me that 3-4 mows was plenty to condition the battery, so I am concerned I got an inexperienced or maybe misinformed agent on the phone.

[jamis]

The way the electronics manage the batteries, conditioning, or formatting, should not be necessary.  What indications are you getting after 15 - 20 minutes of use?  How many bars out on the BLM?  Do the deck motors shut down?  If this were my mower, I'd measure the pack voltage after the charge cycle completes (should be well above 52 volts), right before you mow (should be well above 50 volts) , and after you are done or the mower shuts down (this one is really important).  You can measure the pack voltage at the bottom two contacts of the charging port with a volt meter.  If the voltage is dropping a lot in that 15 minutes, you may have a weak, or failing battery in the pack.  I typically mow for about 45 minutes to mow my yard and the voltage will drop less than 2 volts for that time of mow and have one or no bars out.   I had a battery go bad after 11 months, which Ryobi replaced under warranty, and the mower ran better than when new.  Ryobi walked me through the battery troubleshooting process and that identified the one battery that could not hold its charge under load.  It looked like the battery was weak from the beginning.  I still measure the voltage, hour meter, bars out, and now the percentage at the start and finish of each usage to track any performance trends.  Today, I used my three year old RM480e to mow for 58 minutes and used 1 bar, 2.4 volts, & 2% of the available charge.  If things don't change for you, call Ryobi with the model number, manufacturer number, and serial number from the label under the seat and open a ticket with them to ensure you have warranty coverage.

[JeremyA]

Thanks for your tips. Mowed for about an hour today and had it go down 4 bars... The first 2 went really quick, the third one stayed for 35-40 minutes. Will check the voltages per your suggestion as soon as I locate my multimeter (just moved).

[jamis]

One of things I've learned is these batteries seem to get "lazy" (for the lack of a better term) when they are not used.  During winter storage, the batteries in my mower have required maintenance charges more often as time goes by, but the charges are smaller in wattage.  Then when the mowing season begins, the first few runs seem to use more charge than normal.  However, once usage gets into the normal rhythm of mowing every 4 or 5 days, the batteries return to their normal performance.  Indeed, this year with all of the rain we've had (the area is almost 9" over norm), the batteries are performing better than previous years.  

[jamis]

I mowed today for 1.3 hours by the meter, 81 minutes by my phone, used 3.7 volts of the available charge, with 2 bars out on the BLM, and 82% of the charge left.  The recharge took 2,380 watts and 4 hours to complete.  Cost was $0.31 at my $0.13 per kilowatt hour cost.

[JeremyA]

Found my multimeter - mowed for 80 minutes today(mostly at full speed). Used 5 bars of BLM - voltage dropped from 54.1 at the start to 50.2. I am wondering if they changed the gauge on these mowers. Anyway...it appears to have something near the 2.5 hours of available charge.

[jamis]

The battery meters have changed over the years, but the basic functions haven't.   Ground speed can have a big impact on charge usage.  I can mow for around 80 minutes with my RaM480e and use anywhere from 2 to 4 bars and use 20% to 30% of the charge.  Voltage drop can range from 2.7 volts to 3.7 volts.  All of these were cutting 1/4" to 1/2" off of the grass. I'd say your machine is running to spec.  If you can, try a mow with cruise control on.  If not set too fast, it seems to use the charge a wee bit better.

[JeremyA]

Slowed down and used cruise as much as possible per your instructions - mowed 90 minutes and had voltage drop from 53.8 to 50.9 - still down 5 bars, but 25% less voltage used. Thanks for your help.

[jamis]

Glad it helped. Enjoy.

[jamis]

I have three years of accumulated usage and charge data and I still can't equate voltage usage with percentage left and bars out.  However, the percentage shown on the meter does equate with bars out,  but I still don't know how meter calculates things.  Even bars out doesn't equate to recharge wattage.  It must be something unique to how the SLA/AGM discharge under load.  I have learned that the three different lawn sizes I mow will use varying amounts of charge, no matter what I do.  

[zchild18]

Hi, I have recently been following this thread as I have a the 100Ahr riding mower which I purchased in 2020.  The run time seemed adequate last year, but starting this year the run time is noticeably shorter.  I kept it plugged in all winter long and it's always plugged in when not in use.  I did a pre-mow voltage check a few weeks ago and it was 51.6v.  I mowed until the blades shut off and the post-mow voltage was 49.4v (3 bars left) at which point I drove back to charge it up.  I was able to charge it back up to 100% (voltage was +52v) in about an hour.  Shouldn't the run time be longer if my ending voltage that high still?  Would this be a problem with one of the batteries, or some other problem?  

 

Thanks

[jamis]

A lot of things factor into charge usage, but your description of the blades shutting off at 49.4 volts tells me one of the batteries has developed a weak cell and is not able to support the load of mowing.  The deck blades should shut down closer to 36 volts and two red bars or less.  Once off the load, the voltage will rebound, but drop off as soon as a load is applied.  I had this happen with my RM480e 11 months into use.  Ryobi helped me with troubleshooting.  I charged the batteries and took them to a local battery shop for load testing.  One battery would fail under load, but would slowly take a charge.  The mower runs as good as new at three years.  I'd call Ryobi at the number on the label under the seat with the model number, manufacturer number, and serial number from the label.  They can help you with sourcing a replacement battery.

[jamis]

Since you can measure the voltage, if you can have your meter plugged into the charging port while you turn on the mower and then engage the deck motors, measure the pack voltage at each step.  If the voltage drops, then I'd think there is a weak battery in the pack.  Mine behaved this way until it ultimately failed and the charger started displaying the two red flashes signifying voltage too low (less than 36 volts) for the charger to charge the system.

[zchild18]

I spoke with someone at Ryobi and they suggested I take it to a repair center.  He suggested that one of the controllers might be bad, but I am going to do the battery load test that you have suggested in previous posts.  I suspect it is probably battery related.  Now that we've had a lot of rain, I'll have lots of opportunities to test it out.  Luckily, the repair shop is only a few miles away, so not too big of a deal if I need to take it in.  

[jamis]

Be prepared for the repair center to be not all that knowledgeable on these.  We have four of these on our street and the repair center a mile and a half away has never seen one yet.  Ryobi parts are sometimes backordered too. The center here has seven backpack leaf blowers in their shop waiting on parts.  Ryobi has a 55 page troubleshooting guide that the repair center should have.  If you want a digital copy, message me here with your email address and I'll send it to you.

[jamis]

Just a note to show how the charge usage can vary independent of time, here's the variance after three years of use.  My usual mow is my 10,000 sq.ft. lawn and these are the ranges when 12 of those mows used 1.3 volts:

0 - 2 bars out.

.33 - .80 hours on the meter.

975 - 1,800 watts to recharge.

I get similar ranges for any other volt usages.

[Eric S]

Third summer using my 100ah RM480ex.  I live in western Wisconsin and store the mower in an unheated shed all winter always plugged in.  I mow just about 1 acre and when finished always plug in the charger.  First 2 summers bar wouldn’t drop below 80% charged, however I started noticing about halfway through this summer (2021) my battery percentage would drop to 50%.  I mowed yesterday it dropped to 30% and the blades stopped spinning.  I was about 3/4 done with the yard.  I plugged it in and charged overnight.  This morning the gauge noted 100% battery charged.  I    took off the deck, removed all the accumulated grass from underneath and removed the black covers and removed all the grass on top.  I disconnected the batteries and took them to an auto parts store to get tested.  All 4 batteries were at 13 volts with cold cranking amps of 814, 813, 810 and 775.  650 CCA was set as a baseline.   I called Leoch on the number on the side of the batteries and spoke to Paul this morning.  He told me the battery with 775 CCA “could be suspect” but really no way to tell.  He said 3 years is a good amount of time for those batteries.  I noted how expensive they are and there’s no source to get new ones.  He said he’s fielded quite a few calls from people like me not happy with battery performance.  He of course recommended instead of replacing one battery to change out all four with new ones.  Does anybody know of other battery manufacturers that we can use for our riding mower?  
 

thank you 

Eric

[jamis]

Home Depot is listing SLA/AGM group 24 & 31 batteries that appear to be very similar to the Leoch LPC12s. Prices are $149 & $175 for the 75 ahr. & 100 ahr.  The batteries are by MightyMax and have nearly the same charge cycles as the LPC12s.  No one has said they will work in the Ryobi system. When the battery shop that tested my batteries, their load testing machine showed the failing battery voltage falling as the load was increased.  The Leoch batteries should be good for 1,500 - 1,700 charge cycles, so I replaced the failed battery.  That was two years ago and they are still working well.  I measure each use and all charge cycles and still see very little difference from when the mower was new.  I have 206 charge cycles including winter storage with 150 actual usages.  

[LindaA]

The deck blade motors just whine when I try to mow, with my Riobi RY48ZTR100. I just purchased it this year, any ideas why?

[jamis]

If the blades are not blocked by buildup under the deck and are not spinning, what level of charge is the meter showing?  Otherwise, call Ryobi at the number on the label under the seat.  You will also need the model number, manufacturer number, and serial number from the label when you call.

[Eric S]

If I were to remove the batteries from the rider for the winter, put them in my basement with each battery on an individual trickle chargers/maintainer would that cause damage to the batteries?  

[jamis]

Not sure, however SLA/AGM batteries  do not do well long term when trickle charged.  The technical term is sulfication, which is a buildup of crystals of sulfate on the plates of the cells.  It can shorten the lifespan of some batteries and how they perform.  Ryobi says to charge the batteries individually once a month if removed from the mower with a regular automotive type charger, preferably one with a deep cycle setting.  The Ryobi charging system is designed to automatically charge the battery pack when it falls to 50 volts.  It only uses wall power when a maintenance charge is needed.  This allows the batteries to discharge slightly and then be recharged.  This prevents the sulfication process and lengthens the life  of the batteries.  It's a nice system as it lets you pretty much set it and forget it.  My mower has averaged $1.12 worth of electricity for each 5 month winter storage period in my unheated garage.  I know of one user who is using a large battery blanket during winter storage on his RM480. The important thing is that the batteries should be able to sit for a couple of months before needing a charge.  If a SLA/AGM is allowed to completely discharge, it will be ruined.  

[Eric S]

I attached a Power Pulse earlier this summer time will till if it really works.  I’ll probably end up finishing the fall with the original 4 batteries, keep it plugged in over the winter in my unheated shed and see what happens next spring.  Hopefully if I need to replace a battery it will just be that one reading 775 CCA.  Does anybody know of, or recommend a battery tester that would provide me an indication that the battery is failing or percentage of life left in the battery?

[jamis]

The only test for lead acid batteries I know of is the load test where the test instrument puts a variable load on the fully charged battery and shows  the how the battery responds to the increasing load.  In the case of mine, the voltage fell off dramatically as the load was increased.  The tool the battery shop used to test mine was rather large (almost the size of the battery itself) and far more expensive than I could afford.  Far cheaper to haul the four batteries to the battery shop and let a technician do it.  As for percentage of life left, I don't think there is a way to show it.  After 3 years of recorded data,  I see only a slow trend of increasing watts needed to fully recharge the pack for a given voltage use.  However, it is not linear, nor predictable based on all of the variables in mowing.  One measurement I've followed is the cost per hour to run.  When new, the cost per hour was under $0.20/hr. and three years later, it's under $0.24/hr.  But lately, I've been mowing almost triple the sq.ft. of lawn, so the batteries are being discharged more for each run.  Another parameter I watch is the time between maintenance charges to see the health of the pack.

[jamis]

In case anyone is interested, I spent $30 for a recording electrical meter to record usage parameters for my mower.  It is a Poniie PN2000 meter and it plugs into the wall outlet and the the charger plugs into the meter.  I have it set to show watts and I can see when the charging system draws power from the wall outlet.  Since I park the mower next to the door from the garage into the house, I can see at a glance if the mower has had a charge event when I come into or leave the house.