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diy solar

how old are your flooded batteries

yodamota

Solar Enthusiast
Joined
Dec 9, 2021
Messages
576
Location
Salish sea, British Columbia
So I spent some time trying to find a thread on this. Just wondering how old some of y'alls Flooded lead acid batteries are? I realize use case will be different for each person but I figured just some figures would be handy for people.

Ours are currently 9 years old. 4 -6v Deka solar 370ah batteries. One of the batteries just bit the dust, any load on it drains it very quickly while the others are at 6.3vdc. We were given 4 - 6v rolls batteries by someone who said they were steaming and the water got to low on some of the cells while equalizing. They might be hooped but what the hell(free) They themselves are 10 years old.

I've heard people say they get 13 years from their FLA.

So I am curious to hear how old peoples batteries are.
 
Only use those in golf carts, they tend to last between 3 and 5 years depending on how abused they are and how meticulous the maintenance is.
 
My Trojans about 20 years old. Four or five years ago I just got tired of feeding her water. She got pretty thirsty towards the end. But was still going.
 
So I spent some time trying to find a thread on this. Just wondering how old some of y'alls Flooded lead acid batteries are? I realize use case will be different for each person but I figured just some figures would be handy for people.

Ours are currently 9 years old. 4 -6v Deka solar 370ah batteries. One of the batteries just bit the dust, any load on it drains it very quickly while the others are at 6.3vdc. We were given 4 - 6v rolls batteries by someone who said they were steaming and the water got to low on some of the cells while equalizing. They might be hooped but what the hell(free) They themselves are 10 years old.

I've heard people say they get 13 years from their FLA.

So I am curious to hear how old peoples batteries are.
It’s beyond my ability to understand but this will be my EIGHTH year for using my cheapo FLA husky mower batt….
it’s the same stuff you buy at Walmart for 70 bucks +/- .

The first two years I just parked the mower in Nov and let it sit in the snow all winter…since then I remove the batt and put it on a Battery Tender in my heated shed (40 degrees ) .

Last month I Re- installed it in the mower and cut parts of the pasture twice a week…non huggin . Just bammm…starts right up….

It charges while cutting and then sits Untill I cut again …that’s it…

Very few replaceable things I ever buy seems to last this long…

Wish I understood…

J.
 
I have a 24 year old set of Rolls Batteries that are in amazingly good shape. It's a total outlier but they really are still alive and well.

Granted they've only got a few hundred cycles on them since we are on grid. Long story why I've got these but the short version is they ended up in my possession after a couple trying to build an off grid house had to pause then ultimately abandon thier plans. I was storing them as a favor.

I'm grid tied so other than being pretty much ignored for around 10 years they've had a pretty easy life. I tried to float charge them every so often during that time but to be honest there were 10 to 12 month periods when I just ignored them and didn't even get a chance to float charge them. I finally installed them in my house for back up around 14 years ago.

I try to cycle test them at least once a year. 48v nominal, 1104 AH nameplate rating. When I tested about a year ago I got 700 AH out of then stopped the test because it was getting boring after 3 days. Other than one bad cell which I think I've rejuvenated they are all still behaving well and playing nicely.
 
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Only use those in golf carts, they tend to last between 3 and 5 years depending on how abused they are and how meticulous the maintenance is.
I've dabbled installing off grid solar for others since the mid 90's and saw a lot of FLA batteries that I was either called on to save or install and maintain from new.

I honestly don't think I ever saw a battery die from cycles. Abuse, such as lack of watering or being left at partial state of charge for months, killed a lot but chronic undercharging from WAY to small of a solar array without regular attention to equalization charges was the #1 killer.

I've seen many of the high quality 2v cells go 15 years without any trouble.
 
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Not FLA, but I have a few Optima Blue Tops 12v wired in parallel running my offgrid shop that are 7 years old and running strong. They get discharged to 12.0v nightly.
 
I have a 24 year old set of Rolls Batteries that are in amazingly good shape. It's total outlier but they are really are still alive and well.

Granted they've only got a few hundred cycles on them since we are on grid. Long story why I've got these but the short version is they ended up in my possession after a couple trying to build an off grid house had to pause then ultimately abandon thier plans. I was storing them as a favor.

I'm grid tied so other than being pretty much ignored for around 10 years they've had a pretty easy life. I tried to float charge them every so often during that time but to be honest there were 10 to 12 months period when I just ignored. I finally installed them in my house for back up around 14 years ago.

I try to cycle test them at least once a year. 48v nominal, 1104 AH nameplate rating. When I tested about a year ago I got 700 AH out of then stopped the test because it was getting boring after 3 days. Other than one bad cell which I think I've rejuvenated they are all still behaving.
I have seen those back in the day on major yachts at the marina .

I have owned cars in collage that cost less than those rascals…I just like the way they look…

Great ole battery’s …
 
I sometimes got years out of old sets of used truck batteries.
The secret was to not allow them to discharge too deep.
All they had for a load was a handful of 25 and 40 watt 12 volt incandescent bulbs and now and then maybe a B&W TV for the ball game.

Charging was a 5 hp Briggs and 130 amp alternator run religiously every day.

When cells began to crap out the solution was to drain the electrolyte, wash out the cells and put the batteries in a big steel wash tub boil gently for a couple of hours.
This would break up the surface crud on the plates.

Refill the electrolyte and recharge.
You could get a couple years extra form a worn out set of batteries.
This was my grandfather's old timey ways of getting more life from worn out batteries.
 
I sometimes got years out of old sets of used truck batteries.
The secret was to not allow them to discharge too deep.
All they had for a load was a handful of 25 and 40 watt 12 volt incandescent bulbs and now and then maybe a B&W TV for the ball game.

Charging was a 5 hp Briggs and 130 amp alternator run religiously every day.

When cells began to crap out the solution was to drain the electrolyte, wash out the cells and put the batteries in a big steel wash tub boil gently for a couple of hours.
This would break up the surface crud on the plates.

Refill the electrolyte and recharge.
You could get a couple years extra form a worn out set of batteries.
This was my grandfather's old timey ways of getting more life from worn out batteries.
What do you do with the old electrolyte?
 
I have/had 8 (7 now , 1 went bad about 3 years ago) 4/2005 dated C&D Technologies UPS12-475FR rechargeable sealed lead acid battery's I bought new from a canceled job in the fall of 2005 that I use for backup for my pantry fridge and 3 chest freezers when the power goes out. They only get used a few times a year. I am still using 6 in the pantry and 1 in my 5th wheel. I did a capacity test a few months ago and they still retain a little over 50% of their capacity.
 
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19 years and counting. Got my 48V 625Ah(C/5)/749Ah(C/20) Exide Tudor FLA forklift battery for free over a year ago. It was used on forklift but eventually rejected as it got too weak. It was unused almost a year before I got it. Got it up to 90%SOH but disconnected it from my system for last winter and didn't charge it even once during that ~six months. It's now connected and working again. I seem to get 16,5kWh out of it when discharged down to 47V with ~0,1C. Also need to add ~1L water every other day which is OK as I have my own battery water generator for other reasons. Biggest problem is that my Deye12K (=Sol-Ark15K) is only capable for 60V equalizing voltage which is too low. Need to find cheap 62-63V charger to properly equalize this battery.

Also have ~100kWh of LFPs so never going to get more FLAs anymore. I'm curious (also very cheap) to see how long will this battery survive solar use. Also going to experiment with adding 20kWh LFP parallel to it.
 
Longest service I've had from flooded lead acid batteries is 8 years from Trojan L16s. I did have a Walmart car battery last 9 years in my Toyota pickup.
 
I have had many boats and this one for over 24 years. I have had very expensive batteries and now run inexpensive Wally World batteries. Usually get 4 years out of them. Before ever weekend trip I'll bring out the extension cord and do a overnight charge.

In my quest to make everything solar I decided to use a panel as tire protectors from the sun as well as charger for the batteries. I picked up a Victron SmartCharger 100/15 and was amazed that it didn't have a wet/flooded battery settings. Everything was AGM and LiFeP04.

Now that I am playing with Flooded Lead Acid I figured I would do a deep dive into the settings:
Absorption: 14.7 - 15.0 (14.7)
Absorption time: 4 hrs
Bulk: 14.1 - 14.7 (14.2)
Float: 13.2 - 13.8 (13.5)
Equalize: 15.5 - 15.9 (15.7)
Equalization time: 2-4 hours (Absorption Time/2)
Battery Efficiency: 80%

What do you think?

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I have had many boats and this one for over 24 years. I have had very expensive batteries and now run inexpensive Wally World batteries. Usually get 4 years out of them. Before ever weekend trip I'll bring out the extension cord and do a overnight charge.

In my quest to make everything solar I decided to use a panel as tire protectors from the sun as well as charger for the batteries. I picked up a Victron SmartCharger 100/15 and was amazed that it didn't have a wet/flooded battery settings. Everything was AGM and LiFeP04.

Now that I am playing with Flooded Lead Acid I figured I would do a deep dive into the settings:
Absorption: 14.7 - 15.0 (14.7)
Absorption time: 4 hrs
Bulk: 14.1 - 14.7 (14.2)
Float: 13.2 - 13.8 (13.5)
Equalize: 15.5 - 15.9 (15.7)
Equalization time: 2-4 hours (Absorption Time/2)
Battery Efficiency: 80%

What do you think?

View attachment 213509


With a cool name like Barracudda Bob and the term “Florida Man “ in your location , I felt certain this has to be a boater of some type before I ever read or looked the pic..

I spent several winters at the Dania beach and a few in south Miami on my boat…

Wonderfull times …..

J.
 
So I am curious to hear how old peoples batteries are.

Old people’s batteries certainly are not as sprightly as the whipper snappers but still keep a going, thinking.

Starting about 1996, a pair of Trojan (L16’s?) gave about 13 years of service but the outgassing and increased thirst caused me to switch to AGM. Those were not used a whole bunch and lasted maybe 11 years before replacing. Our limitation is not having a lot of solar (though they usually went to float before 11am majority of days. It is sunny where we live)
 
Now that I am playing with Flooded Lead Acid I figured I would do a deep dive into the settings:
Absorption: 14.7 - 15.0 (14.7)
Absorption time: 4 hrs
Bulk: 14.1 - 14.7 (14.2)
Float: 13.2 - 13.8 (13.5)
Equalize: 15.5 - 15.9 (15.7)
Equalization time: 2-4 hours (Absorption Time/2)
Battery Efficiency: 80%

What do you think?
I like the tire protector idea!

I'd also keep an eye the the specific gravity. You could probably back them down a little bit and reduce watering as long as the SG was in line.

Aren’t the float power requirements for FLA batteries pretty significant?
Depends on the age and condition of the batteries but while they normally aren't terrible they are certainly higher than LFP. A much bigger consideration is the round trip charge/discharge efficiency. Somewhere around 80% is a pretty safe generic number for FLA to use vs. upper 90's for LFP. Both of the numbers are ignoring inverter efficiency since it's the same for either one.

EG: 1kWh of DC energy sent to FLA results on ~.8kWh's of usable DC energy.
 
I haven't measure specific gravity in years. I top them off with distilled every couple of months. I have pick up a kit. Having the solar panel there to protect the tires will probably cause more issue with drying the batteries :fp2 I had thought about putting a fan in the cabin to help keep it cool and dry. Morning dew soaks everything and then the afternoon heat kicks in. I have more power than I need to charge the boat batteries all week. Was also looking at a movable solar structure or even the tilt mounts and tie it back to the LPF. More power in all the wrong places 😇

It was interesting to dive back in the old FLA cells.

 
The correct answer to that is call the toxic taxi.
Back in the bush however thats not practical and it had to be neutralized with baking soda...
I thought it was more complicated than just neutralizing the acid. Seems like an environmental disaster. Just to limp along a battery that’s about done.
 
I thought it was more complicated than just neutralizing the acid. Seems like an environmental disaster. Just to limp along a battery that’s about done.
YA it can be.

Used to be quite easy to just buy new acid and dump it old acid and not worry about the dumping part.
Cottage on an island makes you think a bit more but I can remember the solution to waste oil was to pour it someplace if would soak into the ground to vanish...

Attempts to neutralize it were based around the idea of " you don't want the dogs in it ".

Lead sludge from the bottom of the case, or wash tub and water were dumped on the ground.
I won't lie to you about that
Again we didn't know better, I didn't know better, I was just following direction from a man that told me how he's been doing this since the 1930s,
And not knowing how significant the amounts of spilled acid and lead oxides and sulphur compounds entered the environment never was a thought..

Even now until you really got me to think about it...
I never really thought about what we had been doing.

To keep batteries that are done working.
Again thinking back.
A set of used truck batteries were easy to get and they would often last a couple of seasons if gently used.
What killed them was sulphation and the washout boil out did make them work better.

I did the same with NiCad batteries at work.
No one ever brought up the Cadmium we were dumping.
I wonder would they let us do this today ( probably as long as its under ground there are very few rules about pollution )
 
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I just replaced my 2 Trojan T105s in my camper. They were in year 10 but sparsely used and kept on the charger. May have gotten a year or 2 more out of them but was concerned after the voltage dropped a bit more than normal on very light loads.
 

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