Duracell 6V Golf Cart Batteries

[Ped]

Also most people in campers have at least 8 golf carts.

 

[Red Squirrel]

People here seem to crap a lot on lead acid but they're not THAT bad for the price and easy availability. Lithium is more expensive to buy initially and not as easy to get, and it's a tech that's improving and will probably get cheaper and more available with time but now they are just not as easily obtainable as lead acid. You can't just walk into Canadian Tire to get a Battleborn for example but they'll have loads of lead acid of all kinds. If you run into some kind of deal or something great, but otherwise it's hard to get genuine lithium cells or batteries. Though I did find a site in Canada that sells 18650 lithium Ion which I might experiment with at some point once I get more into electronics so I do design the proper balance charging circuitry and all that. No Lifepo4 though.

I have some RV/Marine batteries in my UPS setup, I should have gotten golf ones but I didn't know any better when I originally setup the system. My 2012 ones died a while back from shorted cell (seems like some kind of bad quality control for these particular ones) but the rest (2013 and newer) have been running ok. Also had one running my shed's solar but I decided to just bring it inside and hook it up to the UPS too instead of replacing the last one that died. Saves me from having to keep up with taking snow off the solar panels. I will eventually automate that. I did keep the battery in the shed for a whole year before that though, there was no load on it but it was trickle charged all year at around 1 watt or whatever little power made it through the snow.

 

[iceledoar]

Side question, how are you monitoring usage? Any one using a shunt, as we FLA users can’t have a fancy BMS.

 

[MrNatural22]

These coulomb meters work well and are budget priced. ?
Many threads on here about this. Do a search.

AiLi Voltmeter Ammeter Voltage Current Meter Voltmeter Ammeter 100V 350A Caravan RV Motorhome 999 AH - - Amazon.com

AiLi Voltmeter Ammeter Voltage Current Meter Voltmeter Ammeter 100V 350A Caravan RV Motorhome 999 AH - - Amazon.com

www.amazon.com

 

[softdown]

Duracell is made by East Penn. The other big lead acid manufacturer is Johnson Controls. It is very hard to beat the GC2 golf cart battery for sheer bang for the buck. They work fine. Plus they are recyclable with no risk of nickel based unstoppable thermal runaway that engulfs the cobalt and creates highly toxic fumes.

People may not always respect LiFePO4/LFP but it is safe and long lasting. Your homeowners policy may require UL rating and I don't think that is available with NMC (nickel manganese cobalt) technology in solar. Or any other Li-Ion - as far as I know.

Right now we can have super high performance with recognizable risk or we can have safety. Choose wisely.

I could argue deep cycle lead acid for a long time. I could argue LiFePO4 for just as long. Depends on your priorities and budget.

 

[carleriksen]

Hi folks,

My name is mIke and I've been using/ selling solar power since 1978. Thought I'd make my first post here about lead acid batteries.

First off, the Duracell batteries from Sam's Club are actually Deka batteries made by East Penn battery company. Are they on the same level as the Dekas? I don't know. I'd say they're not. But at $100 a pop, they're a good value.

Before I retired, I used to be a Trojan battery dealer. I always told my customers, "Only the rich can afford cheap batteries." You certainly get what you pay for. Rural King Ohio as a 6 V golf cart battery for $75. It's rated at 185 Amp/hr.

Are the Trojan T-105 or the T-135 a better battery? They use to be. Trojan has really cheapened their product line during the last several years.

Most, not all, but a good hunk of off brand batteries are made by Exide. Rural King Ohio batteries are mostly rebranded Exide. There are exceptions of course.

Rule of thumb is to not discharge them below 50%. So a 220 amp/hr golf cart battery can only be discharged to 110 amp/hrs without damage. This has been stated before on this thread. Can you do a lower dishcarge? Sure, down to 80% if you want, at the price of reduced life cycles.

"Lead-acid batteries rarely die of old age—They are usually murdered."

The biggest mistake beginners make is not getting the battery charged after it has been drained. Sometimes with solar power, it gets dicey because you might have ten days in a row with cloud cover. Hard to get the batteries charged under those conditions.

The sulfate crystals become harder to break down once they begin growing on the plates. After a while, the battery is unable to accept a charge.

How long will a golf cart battery last in a solar system? Depends... I had 16 of the Duracell batteries that lasted 8 years. They were well cared for.

Mike

Hello Mike, I hope you see this reply to your old post.

I am very interested to see if you would happen to remember the typical DoD you subjected these Duracell GC2's to?

I have gone down the rabbit hole looking at FLA's... oh my... I've finally starting to understand things a bit and it stood out to me several people have had good experience with very well maintained Duracells. I found your post after having on my own concluded that these are Deka GC10's. Some searching and I found specs included life expectancy. I do know that the manufacturers can claim lots of things and life specs vary somewhat greatly. Deka's spec stands out though. They claim abysmal life expectancy.

A few datapoints from the graph: life at 50% DoD - 300 cycles. life at 20% DoD - 800 cycles. Life at 10% DoD 2800 cycles.

Yours lasting 8 years make me suspect this graph is pessimistic. But it is what they published. I understand a rough rule of thumb is to look at the weight for the Ah and these aren't half bad. 60.5 lbs for 215 Ah (@6v).

Did you cycle daily?
What kind of summer weather did they see - very hot or mild?

Best regards
Carl

 

[Prosolar]

Hello Mike, I hope you see this reply to your old post.

I am very interested to see if you would happen to remember the typical DoD you subjected these Duracell GC2's to?

I have gone down the rabbit hole looking at FLA's... oh my... I've finally starting to understand things a bit and it stood out to me several people have had good experience with very well maintained Duracells. I found your post after having on my own concluded that these are Deka GC10's. Some searching and I found specs included life expectancy. I do know that the manufacturers can claim lots of things and life specs vary somewhat greatly. Deka's spec stands out though. They claim abysmal life expectancy.

A few datapoints from the graph: life at 50% DoD - 300 cycles. life at 20% DoD - 800 cycles. Life at 10% DoD 2800 cycles.

Yours lasting 8 years make me suspect this graph is pessimistic. But it is what they published. I understand a rough rule of thumb is to look at the weight for the Ah and these aren't half bad. 60.5 lbs for 215 Ah (@6v).

Did you cycle daily?
What kind of summer weather did they see - very hot or mild?

Best regards
Carl

Hi,Carl,

Yes, I cycled every day. There are several things you must do to get any sort of life from golf cart batteries (and lead acid of any flavor) and that is to get them charged as quickly after a discharge cycle. Many times, especially with under powered solar arrays, that's hard to do. If you can't get them charged, they will sulfate and over several months, they'll lose capacity. I trashed (killed) many a golf cart battery by using a too small PV array to recharge them. Two batteries in series for 12 v at 220amphrs should be hit with at least 25A of charging current. Any less and you won't get them recharged. The longer they sit in a less than fully charge state, is rough on them.

Another reason is the lack of an equalization charge. This is really important! Currently I do a EQ charge at least twice a month. It breaks off any sulfate crystals and stirs the electrolyte.

I got 8+ years out of my last group. They were the Sam's club 220 amp hr golf cart batteries. I had two strings of them for 48V at 440 amp hrs. I did a 50% DOD on them, and once in a while I'd go to 80%.

For the loads I was running, the battery bank was undersized. I could have went with another strings, but good design limits the number of parallel strings to three. More than that, it's time to upgrade the size of your batteries. Go from golf cart to L16s for example.

I don't know about the specs you have listed. That's a piss poor amount of cycles. But then if you were to put them in golf carts, and you did one cycle per day then you'd get two years of service out of one set per golf cart. I figured 150 days of use, about a summer's worth of work.

My batteries lived in the garage. In the summer it was hot, and winter it was cold. The Midnite solar Classic reports that the batteries are at 87ºF this afternoon.

My advice for long lead acid life is simple.
Get them charged as quickly as you can. Don't leave them in a partial state of charge
Equalize them on a regulator basis. It's free!
Keep the tops clean. You'd be surprised how much more energy they will lose when the top is covered in acid mist.
Use a hydrometer to check the cells. Record the results. If you see an issue, you might be able to do an EQ and balance the cells within the battery.

Lithium batteries are the current buzz, and you'd be surprise how I have been attacked for my posting of lead acid batteries. For me, although they are old school, they are hard to beat in stationary energy storage. That's why most telecom systems still use lead acid AGM batteries.

Hope this helps
Mike

 

[12VoltInstalls]

As for lead/acid, the 4x rule can't be broken

Sure it can. Cuz it’s not a rule

but for OP’s situation those AGMs are a much better choice due to unknown commitment to distilled water use.

get them charged as quickly after a discharge cycle. Many times, especially with under powered solar arrays, that's hard

100% agree. That and your equalize comment.

Thankfully there’s many lead acid batteries that are unaware of the rules that people who don’t like lead acid batteries try to apply to them.

 

[Wellbuilt]

Hmmmm my Duracell golf cart batteries are
215 ah
I use 2 strings of 8 battery’s for 48 volt
430 ah system .
I am finishing my third season .
I run a 2800 sf cabin with them .
I have zero problem with them I use 10%
Over night and down to 20% in the winter .
I run frig / freezer chest freezer water pump tv 60 plus lites microwave and 3 ceiling fans .
I have no problem with them I checked the water in may and added 11/2 gallons , I just checked them for water and I’m down 1/4 to 3/8 “ so not bad .
I payed 1500$ bucks
These battery like to be charged hard.
Instead of EQing I leave them on float for a few days when i go home .
They get 2 good eqs spring and fall .
I have 4500 watts of solar

 

[carleriksen]

Hi,Carl,

Yes, I cycled every day. There are several things you must do to get any sort of life from golf cart batteries (and lead acid of any flavor) and that is to get them charged as quickly after a discharge cycle. Many times, especially with under powered solar arrays, that's hard to do. If you can't get them charged, they will sulfate and over several months, they'll lose capacity. I trashed (killed) many a golf cart battery by using a too small PV array to recharge them. Two batteries in series for 12 v at 220amphrs should be hit with at least 25A of charging current. Any less and you won't get them recharged. The longer they sit in a less than fully charge state, is rough on them.

Another reason is the lack of an equalization charge. This is really important! Currently I do a EQ charge at least twice a month. It breaks off any sulfate crystals and stirs the electrolyte.

I got 8+ years out of my last group. They were the Sam's club 220 amp hr golf cart batteries. I had two strings of them for 48V at 440 amp hrs. I did a 50% DOD on them, and once in a while I'd go to 80%.

For the loads I was running, the battery bank was undersized. I could have went with another strings, but good design limits the number of parallel strings to three. More than that, it's time to upgrade the size of your batteries. Go from golf cart to L16s for example.

I don't know about the specs you have listed. That's a piss poor amount of cycles. But then if you were to put them in golf carts, and you did one cycle per day then you'd get two years of service out of one set per golf cart. I figured 150 days of use, about a summer's worth of work.

My batteries lived in the garage. In the summer it was hot, and winter it was cold. The Midnite solar Classic reports that the batteries are at 87ºF this afternoon.

My advice for long lead acid life is simple.
Get them charged as quickly as you can. Don't leave them in a partial state of charge
Equalize them on a regulator basis. It's free!
Keep the tops clean. You'd be surprised how much more energy they will lose when the top is covered in acid mist.
Use a hydrometer to check the cells. Record the results. If you see an issue, you might be able to do an EQ and balance the cells within the battery.

Lithium batteries are the current buzz, and you'd be surprise how I have been attacked for my posting of lead acid batteries. For me, although they are old school, they are hard to beat in stationary energy storage. That's why most telecom systems still use lead acid AGM batteries.

Hope this helps
Mike

Hi Mike,
Thank you very much for you detailed response; it does very much help!

I have done a great deal of research, I am generally good at digging out what I am searching for even if the knowledge/information is sometimes obscured or dispersed. But fully detailed use cases are hard to come by, so thank you very much for yours. What you write above touches on pretty much everything I have been able to synthesize from a great many resources and forum posts. I had come to the conclusion that it is, as you detail, paramount to be generous with your panel wattage. This is only becoming easier as $/w goes down with better and better panels. Failure to consistently fully charge is to fail. Your specific experience is a very welcome data-set that backs up what I had come to understand in bits and pieces - both from failure use cases and success use cases around the web.

It is very interesting that you have gotten above 3000 cycles with 50% DOD. That is very strong performance. That comes close to rivaling the published performance (accelerated ageing) for Trojan IND line! Nothing short of impressive and exciting. (given that people could be skeptical of such performance I want to emphasize my statement is genuine, not sarcastic). Makes you wonder what those high quality batteries could do in the hands of the right person.

Note taken of your EQ regime, you must be doing the right things throughout.

I agree on your take on the specs I listed, it makes no sense. How could they possibly have come to that conclusion? But as an engineer I am all for putting all information available on the table so what needs to be discredited can. I don't think I can post a link, but if you search in google, copy this Sam's Club/Deka/Duracell/EastPenn 6V GC2 specs and your first search result should link you to a forum post in forestriverRV forum that contain a link to the spec as published. Your data invalidates this, but for completeness/interest it's there to see.

It gets all the more impressive with the temperature you have recorded. That is supposed to significantly shorten life expectancy; yet you got 8 plus years. On top of this you have two parallel strings! Have you ever had any negative effects of the parallel setup?
I feel the need to ask but with the lifespan I imagine no.

Your advice for proper care is very straightforward and could not be stated simpler. How would this be too much work compared to programming and managing BMS lithium setups?

Have you considered/used automatic watering? Or is it in your opinion not worth the expense for a perhaps pretty easy/not too frequent task?

Yes, lithium is all the buzz. It is exciting. New technology is a promising thing and I have nothing against it. It is unfortunate though that excitement tends to run ahead of thoroughness and impartial investigation. I think a big missing link in the DIY sphere is giving Lead-Acid a fresh look, what can it do today rather that judge it on preconceived notion. If LA were treated with the same innovation/craftiness and vigor as is homebuilt Li packs, where would LA stand? I don't mean build your own LA battery, but more in the realm of how can we extract better performance. I tend to be the type that notices what gets missed so hence my interest in what can LA really do.

Thank you
Carl

 

[Prosolar]

Hi Mike,
Thank you very much for you detailed response; it does very much help!

I have done a great deal of research, I am generally good at digging out what I am searching for even if the knowledge/information is sometimes obscured or dispersed. But fully detailed use cases are hard to come by, so thank you very much for yours. What you write above touches on pretty much everything I have been able to synthesize from a great many resources and forum posts. I had come to the conclusion that it is, as you detail, paramount to be generous with your panel wattage. This is only becoming easier as $/w goes down with better and better panels. Failure to consistently fully charge is to fail. Your specific experience is a very welcome data-set that backs up what I had come to understand in bits and pieces - both from failure use cases and success use cases around the web.

It is very interesting that you have gotten above 3000 cycles with 50% DOD. That is very strong performance. That comes close to rivaling the published performance (accelerated ageing) for Trojan IND line! Nothing short of impressive and exciting. (given that people could be skeptical of such performance I want to emphasize my statement is genuine, not sarcastic). Makes you wonder what those high quality batteries could do in the hands of the right person.

Note taken of your EQ regime, you must be doing the right things throughout.

I agree on your take on the specs I listed, it makes no sense. How could they possibly have come to that conclusion? But as an engineer I am all for putting all information available on the table so what needs to be discredited can. I don't think I can post a link, but if you search in google, copy this Sam's Club/Deka/Duracell/EastPenn 6V GC2 specs and your first search result should link you to a forum post in forestriverRV forum that contain a link to the spec as published. Your data invalidates this, but for completeness/interest it's there to see.

It gets all the more impressive with the temperature you have recorded. That is supposed to significantly shorten life expectancy; yet you got 8 plus years. On top of this you have two parallel strings! Have you ever had any negative effects of the parallel setup?
I feel the need to ask but with the lifespan I imagine no.

Your advice for proper care is very straightforward and could not be stated simpler. How would this be too much work compared to programming and managing BMS lithium setups?

Have you considered/used automatic watering? Or is it in your opinion not worth the expense for a perhaps pretty easy/not too frequent task?

Yes, lithium is all the buzz. It is exciting. New technology is a promising thing and I have nothing against it. It is unfortunate though that excitement tends to run ahead of thoroughness and impartial investigation. I think a big missing link in the DIY sphere is giving Lead-Acid a fresh look, what can it do today rather that judge it on preconceived notion. If LA were treated with the same innovation/craftiness and vigor as is homebuilt Li packs, where would LA stand? I don't mean build your own LA battery, but more in the realm of how can we extract better performance. I tend to be the type that notices what gets missed so hence my interest in what can LA really do.

Thank you
Carl

Hi, Carl...
You bring to the table many good ideas and questions.

Set your wayback machine to 1983, and the cost of a 35 W solar panel was around $600. I don't know what that would cost in today's money, but let me tell you, I was selling PV back in '83 and $600 was a whale of a lot of money. For your $600 bucks, you got one solar panel that did about 2 A. The popular, at the time, ARCO 16-2000 did just that—16 V at 2000 mA—thus its name.

Even if you had the money and purchased four to six of those panels, you were only able to squirt in 8/12A on a good day. Now, you're charging a set of two golf cart batteries that you're sucking dry every night or so. Twelve amps won't do you much good and after a year or if you're lucky, two, those batteries were toast.

Now you have to also remember that the price of lead acid batteries in '83 were dirt cheap! A trojan T-105 hit you for forty and change!

Back then, only the super rich could afford enough solar to keep a set of LA golf cart batteries fully charged and healthy. Up until let's say five/eight years ago, the price of PV panels were still damn awful expensive.

Now, returning to the present, I should clarify that during times of low solar, I didn't discharge the batteries too deeply. If I had a week of rain/snow, I disconnected the load and let the batteries float on whatever was coming in from the array.

With the price of PV dropping like a rock, you can get used panels from Santan Solar for less than $40 a panel now, unless you don't have the space, you can add enough solar to your setup to keep those batteries fully charged.

My wife and I are still on the grid, and we use a 10kWp grid tie along with 7kWp of battery off grid. Around end of February, I go off grid and on the batteries until the weather changes for crap sometime in october. Then I watch the state of charge and the depth of discharge and go back onto the gird as needed.

My current utility charges me $.06 per kWh and the batteries cost my $5600. Kill the batteries or pay Ohio Edison $.06? Hummm... what to do?

If I had a setup of dozens of batteries, then I'd consider an automatic watering system. Too many wrenches in the machine certainly increases the chance of something going wrong.

Personally, I enjoy working with the batteries and make it a point to check water levels every two weeks. I do one check before I equalize and one after equalization.

Temperature is the one factor that I see as a issue with Lithium batteries. They simply don't like to get cold. To me, it seems to be self defeating to use their own energy to keep them warm (via heat tape, blankets or what nots.)

And I can't argue that Lithium batteries are superior in many ways. However that being said, the price point is still outside for most of us. My 25kWh worth of lead acid storage (the 50% DOD already figured in) cost me $5600. To get that much storage in a lithium setup would push the price to around $30K. That's not reasonable by anyone's measure. Especially considering the price I pay for gird power is $.06 a kWh.

Chinese cells for a third of that? I guess so. Lots of people are doing that. At this time, I'm seeing the light at the end of my tunnel, I'm working on other solar electric projects.

Mike

 

[carleriksen]

Hi, Carl...
You bring to the table many good ideas and questions.

Set your wayback machine to 1983, and the cost of a 35 W solar panel was around $600. I don't know what that would cost in today's money, but let me tell you, I was selling PV back in '83 and $600 was a whale of a lot of money. For your $600 bucks, you got one solar panel that did about 2 A. The popular, at the time, ARCO 16-2000 did just that—16 V at 2000 mA—thus its name.

Even if you had the money and purchased four to six of those panels, you were only able to squirt in 8/12A on a good day. Now, you're charging a set of two golf cart batteries that you're sucking dry every night or so. Twelve amps won't do you much good and after a year or if you're lucky, two, those batteries were toast.

Now you have to also remember that the price of lead acid batteries in '83 were dirt cheap! A trojan T-105 hit you for forty and change!

Back then, only the super rich could afford enough solar to keep a set of LA golf cart batteries fully charged and healthy. Up until let's say five/eight years ago, the price of PV panels were still damn awful expensive.

Now, returning to the present, I should clarify that during times of low solar, I didn't discharge the batteries too deeply. If I had a week of rain/snow, I disconnected the load and let the batteries float on whatever was coming in from the array.

With the price of PV dropping like a rock, you can get used panels from Santan Solar for less than $40 a panel now, unless you don't have the space, you can add enough solar to your setup to keep those batteries fully charged.

My wife and I are still on the grid, and we use a 10kWp grid tie along with 7kWp of battery off grid. Around end of February, I go off grid and on the batteries until the weather changes for crap sometime in october. Then I watch the state of charge and the depth of discharge and go back onto the gird as needed.

My current utility charges me $.06 per kWh and the batteries cost my $5600. Kill the batteries or pay Ohio Edison $.06? Hummm... what to do?

If I had a setup of dozens of batteries, then I'd consider an automatic watering system. Too many wrenches in the machine certainly increases the chance of something going wrong.

Personally, I enjoy working with the batteries and make it a point to check water levels every two weeks. I do one check before I equalize and one after equalization.

Temperature is the one factor that I see as a issue with Lithium batteries. They simply don't like to get cold. To me, it seems to be self defeating to use their own energy to keep them warm (via heat tape, blankets or what nots.)

And I can't argue that Lithium batteries are superior in many ways. However that being said, the price point is still outside for most of us. My 25kWh worth of lead acid storage (the 50% DOD already figured in) cost me $5600. To get that much storage in a lithium setup would push the price to around $30K. That's not reasonable by anyone's measure. Especially considering the price I pay for gird power is $.06 a kWh.

Chinese cells for a third of that? I guess so. Lots of people are doing that. At this time, I'm seeing the light at the end of my tunnel, I'm working on other solar electric projects.

Mike

Hi Mike,

Yes, the historical context is quite something. When some lament how batteries have gone up in price it is important to remember how much more panel wattage price has fallen. Your chance of maintaining the batteries are so much better now, plus you can have panel wattage surplus for consumption. A little load planning would go a long way.

I am thinking the way to go is to be a generation behind and use older used solar panels, looks like optimum right now is ~250w panels. Packaged lots can be found on ebay as well.

I think your joy of maintaining the batteries has a lot to do with the ability to keep them this long. Having an active interest matters. Right now most peoples active interest seems to be diy Li packs, which is complete ok, but not a fair comparison to LA packs that often suffer from lack active interest.

The system I want to build would see a use just like yours. I don't need to have a solar system, I have grid. I will never benefit finacially, I will likely pay more per KWh. I am doing it to have an active (partial) backup system and out of wanting to tinker.