Finding 6v GC2 batteries at Costco?

[sonofcy]

Originally Posted by cookinwitdiesel

What lithiums did you go with?

We will not be doing the install until Oct 2021 due to needing about $33,000 CDN to pay for everything, but as of yesterday AM Solar is recommending for our system the Life Blue would be best. For larger systems they would go Victron. One requirement we have is cold weather camping. We will store the batteries inside the camper so physical size and weight are a consideration. This is why the 200AH are a good fit, at about 60 lbs each I can still move them if needed. They will go under our MBR couch in front of our front window. BTW, that weight of 180 lbs is 60 lbs less than the FLA supplying only 450 AH.

[sonofcy]

Actually we are now talking charger not converter. Most have a default program so no need for questions, but yes for those who want to get the most from their system then finding that information would take them 5 or 10 minutes of searching for sure. Trojan provides everything you need on their web site as do most if not all the other providers of GC2's (most core's actually made by Trojan). As I said if you are just a weekender plus two weeks vacation then just leave it alone, but if you have serious usage you will have to install the needed equipment unless you do not use much electricity. I wintered the last two years on Vancouver Island and lived through several power outages of several days. The dealer installed batteries would have lasted 2 hours as opposed to the 6 we got out of a pair of T105's only using 30%. I then fired up the two Honda EU2000's and plugged in the 50 to 30 adapter. That took another 6 hours to recharge the batteries (I was only going from 70% to 100% DOD). Of course if you do not have a Trimetric TM-2030-RV you have no idea how your batteries are doing. I bought my Trimetric before I bought my RV, that's how valuable it is to this old electrician.

[cookinwitdiesel]

I bought a Victron BMV-712 battery monitor but haven't installed it yet. Will probably do that and some bus bars soon. All that in preparation for some batteries (likely BattleBorns) and Victron MultiPlus Inverters (thinking 2x 24v/3000kVA - one servicing each leg of the 240v service, and the needed 24v->12v DC converter to power the rest of the trailer).

Down the road, I would like to add solar but can easily do that later, batteries and inverter work for now, with recharge at sites every few days as needed or just run the generator to top off the batteries.

I know that is a lot of gear and money, but given my wife has mandated I will have this trailer for 10 years, I am pretty confident with the investment.

[sonofcy]

[QUOTE=travelin texans;347875]

Originally Posted by sonofcy

Better would be programmable with temperature compensation, that's not a Ford, RAM, GM thing, it's more like a 1920's Ford vs 2020's Ford

That would be just one more thing that most folks would never figure out & there'd be 100s of post on here of "how to I program my convertor?". The 3 stage that if plugged into shore power does it's thing on the last 3-4 rvs I've had & I didn't have even have to think about it. Simple is best!
Look how many posts just in the past couple months concerning the In Command system. Great idea to try & attract the millennials with high tech gadgets, but that's not the ones buying the majority of the rvs.
As for lithium batteries, I got just shy of 6 years fulltiming from the pair of no name batteries the dealer installed, no way would I, even if money was no object, be spending $300-400 each for lithium.

The lithium's cost closer to $1,000 per 100AH. Still the same 1,000 cycle life time cost as FLA and actually 60% of FLA at the more realistic 5,000 cycle lithium life. Again, if you are not full time then it probably doesn't matter to you, we are 365 days a year in our RV. If you are just relying on the idiot lights, then you know how unreliable they are. As far as inCommand, yes I wish there had been a manual switch option, but this is another way the industry is trying to keep the costs down and wasn't an option. So far other than a spat of Bluetooth problems that have gone away it has been 100% reliable for the almost two years we have been in it. Remember some fulltimer's need the RV furnace and one night of that will kill the dealer installed battery in one night, so we have to install better batteries as a minimum. Also many full timers (my wife) like the much better residential refrigerator option and that uses 1.5Kwh per day or 4 times the full capacity of the dealer batteries or one full pair of T105's (all at 50% DOD). There is a huge difference between full time living and recreational use. Keep that in mind.

[sonofcy]

Originally Posted by cookinwitdiesel

I bought a Victron BMV-712 battery monitor but haven't installed it yet. Will probably do that and some bus bars soon. All that in preparation for some batteries (likely BattleBorns) and Victron MultiPlus Inverters (thinking 2x 24v/3000kVA - one servicing each leg of the 240v service, and the needed 24v->12v DC converter to power the rest of the trailer).

Down the road, I would like to add solar but can easily do that later, batteries and inverter work for now, with recharge at sites every few days as needed or just run the generator to top off the batteries.

I know that is a lot of gear and money, but given my wife has mandated I will have this trailer for 10 years, I am pretty confident with the investment.

Wow, that's quite the setup. Check out AM Solar for some ideas. You don't need 2 inverters to power both legs, you can just hook up the inverter like a 50A to 30A dogbone. AM even has a smart auto switch in addition to your transfer switch. If you need 6,000 watts then by all means use two 3,000 W units but that implies you are using everything on your power panel so will need a LOT of lithium, maybe 10 or more. I am making a couple of power panel swaps so I will only power one leg and provide custom wiring from the inverter to the panel (no 50 to 30 jumper)

[cookinwitdiesel]

I will take a look at AM solar, thanks!

[JRTJH]

Originally Posted by sonofcy

Better would be programmable with temperature compensation, that's not a Ford, RAM, GM thing, it's more like a 1920's Ford vs 2020's Ford thing.

You are right, but finding a "competitive price" on a programmable/temperature compensating converter charger that's "plug and play" for the RV market is daunting, especially for the RV owner who has little or no experience in the "hybrid AC/DC systems" that are used in nearly all RV's.

Honestly, for most people who own RV's, it makes little difference if they have a $3000 lithium battery system or a $300 FLA battery system, as long as the lights turn on when DW flips the switch, the system is "good enough for us".... It's the "cutting edge owner" who has an unlimited budget and wants "only the latest and greatest" that finds a programmable/temperature compensation converter/charger to be a "smart mod".....

[mfifield01]

Just checked my Costco today. They didn't have any sitting out. They said they just got them in the back $89.99. I purchased some about 3 years ago ($83.99 at the time).

[Mainer]

Just had a Sam's Club GC2 fail at camp (solar installation)... One of a series connected 12 volt system. Electrolyte was a little low when we arrived this spring, but above the plates. Had been charging at a higher voltage due to high internal resistance for some time, it also killed a 6 volt trail camera. Can't complain much, it was at least 8 years old. Sprang for 2 new AGM batteries. Difference in price was about what the truck burned in gas to get them so we would have lights that night.

[SR71 Jet Mech]

Hmmm, my 2016 Sprinter fiver came with a WFCO 9855 converter/charger... 50a service, 55 amp 12vdc. There is no “3 stages” . It has 2, 13.6 v and floats at 13.1. A good charger will hit 14.6v in absorption cycle to actually fully charge batteries. I have 2 chargers. Replaced the converter with a 4 stage and added an inverter charger, also 4 stage. There isn’t any “programming “, read the book and pick a number the correlates to the type of battery. Move selector to the number and that’s it. On both.
I too have 4 Duracell 230ah batteries at $110 each from batteries plus. Seem to work well so far. Will wait for lithium price to come waaaay down before considering.
Interesting read here though.
Also my two Victron solar chargers set the same way and temp control is performed automatically through the chargers. Pulls current back during charging to keep from over gassing batteries. (I think). Pretty simple.
Battery monitor is a must too.

Scott

[cookinwitdiesel]

I am currently leaning towards getting a bunch of 6v batteries (8-12) and making a large 24v bank (smaller wiring needed to inverters) and then I can add in the Lithiums at a later date. This would allow me to split up the inverter and battery purchase (all of those 6Vs would be less than a single Lithium battery).

If I am doing the math right, 8x 6v batteries at ~200Ah each would give me the same run time as 4x 24v 50Ah Lithiums.

And that all sounded great in my head until I did the math....that is 600# of batteries nevermind having to maintain fluid levels on 8 batteries as well as managing mid-point voltages and a ton of additional wiring and where would they all go and....

Nevermind haha

[SR71 Jet Mech]

Yeah the weight is a tough deal. @ 77pounds each I stopped at 4. With a residential fridge I can easily make it over night and be around 70% SOC remaining in the bank. No problem running microwave or coffee maker. With the 85a charge rate2500 w inverter charger ( and a cloudy day) I’m able to top off bank in about 3 hours with a 2kw champion gen. With sun and atmosphere allowing say 80% efficiency on solar, it takes about 6-7 hours. Can run one a/c (with good sun) for extended periods but no electric heaters.
It’s hard to add too many batteries in any towable RV due to weight and space. I’m using this RV as a test dummy for the next. Biggest and best lesson learned so far is NO RESIDENTIAL FRIDGE!

Scott

[sonofcy]

Are you full time? What battery monitor are you using? Charging back up 30% DOD in 3 hours for FLA does not make sense to me, my experience is double that time with half that bank at same DOD using a Trimetric TM-2030-RV. We love our residential fridge, an RV fridge is a good cooler. Yes it uses 1.5Kwh per day but that's less than 1 lithium as long as there is a bit of sun and the lithium's charge curve is a straight line so they recharge MUCH faster.

[SR71 Jet Mech]

No sonofcy we don’t full time yet. 30% of 460ah bank is 138ah used. I set the charge rate at 60 amps not the full 85. I’m way under the maximum charge rate for this bank. not any different than the WFCO 9885 mentioned above. I watch my monitor and increase or decrease depending on other draws to keep it at or below a 20% charge rate. If the bank gets too warm the temp feature will drop the current to compensate. I use a monitor from thornwavelabs.com. Works exactly the same as a victron712 or trimetric. Only way less $$.

Yes I agree the lithium batteries do charge faster and you can draw them down to almost nothing.

We do spend a lot of time in our RV though, home a week, gone a week all spring, summer and fall. Wishing we could be full time. Boondock half of it.

I thought I had done some pretty good research on this whole battery, solar, inverter, converter deal but, seems every time I try to give my $.02 ( thinking I may help someone) I get bashed from someone. I’ve enjoyed reading and following along but I gotta say feeling welcome here isn’t for everyone. My system is a work in progress as I’ve stated. But it seems to need a reboot and I need a new career.

It’s been a slice.....


Scott

[SR71 Jet Mech]

Lead Acid

“Before connecting the battery, calculate the charge voltage according to the number of cells in series, and then set the desired voltage and current limit. To charge a 12-volt lead acid battery (six cells) to a voltage limit of 2.40V, set the voltage to 14.40V (6 x 2.40). Select the charge current according to battery size. For lead acid, this is between 10 and 30 percent of the rated capacity. A 10Ah battery at 30 percent charges at about 3A; the percentage can be lower. An 80Ah starter battery may charge at 8A. (A 10 percent charge rate is equal to 0.1C.)”

Again maybe I’m all wet but this is a sample of the research I have done on charge rates.

[sonofcy]

Originally Posted by SR71 Jet Mech

Lead Acid

“Before connecting the battery, calculate the charge voltage according to the number of cells in series, and then set the desired voltage and current limit. To charge a 12-volt lead acid battery (six cells) to a voltage limit of 2.40V, set the voltage to 14.40V (6 x 2.40). Select the charge current according to battery size. For lead acid, this is between 10 and 30 percent of the rated capacity. A 10Ah battery at 30 percent charges at about 3A; the percentage can be lower. An 80Ah starter battery may charge at 8A. (A 10 percent charge rate is equal to 0.1C.)”

Again maybe I’m all wet but this is a sample of the research I have done on charge rates.

A couple of points. I don't know of any RV that comes with a programmable charger. Perhaps you will share info on your programmable charger including cost. As far as charging rates just go to the battery makers website and it will be listed there. If you have several batteries in parallel then the charge rate to program is for the total bank. In my case when I get my lithium's which charge at between 0.5C and 1C depending on ??? then a 600AH bank could be charged with a 300 or 600 amp charger in 1 or 2 hours. The problem is nobody makes a charger that big for this application. 120A seems to be about it for a 3,000W inverter so charging from 0 to 100% in 5 hours is fine with me. Of course most of the time the sun will be our charger and coincidently I have enough room for a 120A solar setup.

[SR71 Jet Mech]

BATTERY CHARGING TUTORIAL

Current battery charging technology relies on microprocessors (computer chips) to recharge, using 3 stage (or 2 or 4 stage) regulated charging. These are the "smart chargers", and quality units generally are not found in discount stores. The three stages or steps in lead/acid battery charging are bulk, absorption, and float. Qualification, or equalization are sometimes considered another stage. A 2 stage unit will have bulk and float stages. It is important to use battery manufacturer's recommendations on charging procedures and voltages, or a quality microprocessor controlled charger to maintain battery capacity and service life.
The "smart chargers" are profiled with contemporary charging philosophy in mind, and also take information from the battery to provide maximum charge benefit with minimum observation. Some gel cell and AGM batteries may require special settings or chargers. Our units are selected for their suitability on the battery types they specify. Gel batteries generally require a specific charge profile, and a gel specific or gel selectable or gel suitable charger is called for. The peak charging voltage for Gel batteries is 14.1 or 14.4 volts, which is lower than a wet or AGM type battery needs for a full charge. Exceeding this voltage in a Gel battery can cause bubbles in the electrolyte gel, and permanent damage.
Most battery manufacturers recommend sizing the charger at about 25% of the battery capacity (ah = amp hour capacity). Thus, a 100 ah battery would take about a 25 amp charger (or less). Larger chargers may be used to decrease charge time, but may decrease battery life. Smaller chargers are fine for long term floating, e.g. a 1 or 2 amp "smart charger" can be used for battery maintenance between higher amp cycle use. Some batteries specify 10% of capacity (.1 X C) as the charge rate, and while this doesn't hurt anything, a good microprocessor charger of the appropriate charge profile should be fine up to the 25% rate. You talk to different engineers, even at the same company, you get different answers.

Here’s another but the last sentence is the key....

[SR71 Jet Mech]

I have 4 different chargers in my rv none of which are original. The solar is set up into two arrays, one is 600w with a 100/50 victron/blue solar mppt charger ($323ish), the other is a 500 w array set up on a solar epic 40 amp mppt ($250ish). My inverter charger is an Aims 2500w/85 amp charger/pure sine wave inverter ( $600 ish). I replaced the 2 stage converter with a 4 stage 55 amp converter @ around $200 (don’t remember the brand but can look it up if it really matters). I use a thornwave labs battery monitor. 500 amp shunt. 2/0 cable at a 4 foot length max. 8awg cable on solar panels all tied in series. The coach also came with an inverter (1kw) for the fridge
At 20% my charge rate should be 92a on a 460 ah bank. I don’t have the capacity to get that high.
Not sure why you’re bringing the lithium batteries into this as all I ever said is right now they’re too pricey for me. Wish I was a rich man but my budget allows only FLA at this time. Would love to have lithium’s.
Yes battery manufacturers all have their own charging specs. A Trojan battery make up is no different than a Duracell or a Dekka and a20% charge rate is pretty standard on a flooded lead acid battery at 14.4-14.6v max.

You are correct that I too do not believe any coach comes with a programmable charger “factory installed “. Did I say that somewhere? Most if not all only bulk charge at a maximum rate of 13.6-13.8 v then float at 13.1-13.2v. That’s it.
Hence the reason I replaced mine.

So in the end, I sized my equipment to stay at or under the 20% rate of MY bank. It’s all just a math problem. I too have room for much solar however I choose to not permanently mount mine to the coach. My limit is space and weight so 4 batteries is it for now. More than enough and we use everything in our coach except the electric fireplace. I have monitored it all closely for going on 3 years now and it seems to work well. Total in my system now is around $4k down to every little fuse and connector.

Now it’s a matter of trying different panels to get the best bang for my buck and refining my system to its full potential.

And I will share ALL my info at anytime with all, that’s why I joined this forum. To learn and to teach or help.

But for some reason when on the battery/solar/charging subjects there is someone like you that wants to butt heads.

I work in a factory that has approximately 200 items from man lifts to tuggers to forklifts, some 12v, some 24v, some 36 volt, some 48 v. From 230 ah to 1250 ah banks or single batteries. All FLA. 17 different brands of chargers from transformer style to inverter style. I by far will be the first to admit I don’t know everything but, I have a grasp on batteries and chargers and charging algorithms. I also check regularly with a hydrometer and equalize based on that not just at a predetermined interval. With the proper maintenance I’ve seen FLA batteries run 15 years. Capacity will drop but will still maintain about 80-85% of original state. Keep from sulfating, keep water level up and maintain specific gravity. Oh and set charge rates correctly and use a “smart” charger.

Time to move on......

[sonofcy]

Originally Posted by SR71 Jet Mech

I have 4 different chargers in my rv none of which are original. The solar is set up into two arrays, one is 600w with a 100/50 victron/blue solar mppt charger ($323ish), the other is a 500 w array set up on a solar epic 40 amp mppt ($250ish). My inverter charger is an Aims 2500w/85 amp charger/pure sine wave inverter ( $600 ish). I replaced the 2 stage converter with a 4 stage 55 amp converter @ around $200 (don’t remember the brand but can look it up if it really matters). I use a thornwave labs battery monitor. 500 amp shunt. 2/0 cable at a 4 foot length max. 8awg cable on solar panels all tied in series. The coach also came with an inverter (1kw) for the fridge
At 20% my charge rate should be 92a on a 460 ah bank. I don’t have the capacity to get that high.
Not sure why you’re bringing the lithium batteries into this as all I ever said is right now they’re too pricey for me. Wish I was a rich man but my budget allows only FLA at this time. Would love to have lithium’s.
Yes battery manufacturers all have their own charging specs. A Trojan battery make up is no different than a Duracell or a Dekka and a20% charge rate is pretty standard on a flooded lead acid battery at 14.4-14.6v max.

You are correct that I too do not believe any coach comes with a programmable charger “factory installed “. Did I say that somewhere? Most if not all only bulk charge at a maximum rate of 13.6-13.8 v then float at 13.1-13.2v. That’s it.
Hence the reason I replaced mine.

So in the end, I sized my equipment to stay at or under the 20% rate of MY bank. It’s all just a math problem. I too have room for much solar however I choose to not permanently mount mine to the coach. My limit is space and weight so 4 batteries is it for now. More than enough and we use everything in our coach except the electric fireplace. I have monitored it all closely for going on 3 years now and it seems to work well. Total in my system now is around $4k down to every little fuse and connector.

Now it’s a matter of trying different panels to get the best bang for my buck and refining my system to its full potential.

And I will share ALL my info at anytime with all, that’s why I joined this forum. To learn and to teach or help.

But for some reason when on the battery/solar/charging subjects there is someone like you that wants to butt heads.

I work in a factory that has approximately 200 items from man lifts to tuggers to forklifts, some 12v, some 24v, some 36 volt, some 48 v. From 230 ah to 1250 ah banks or single batteries. All FLA. 17 different brands of chargers from transformer style to inverter style. I by far will be the first to admit I don’t know everything but, I have a grasp on batteries and chargers and charging algorithms. I also check regularly with a hydrometer and equalize based on that not just at a predetermined interval. With the proper maintenance I’ve seen FLA batteries run 15 years. Capacity will drop but will still maintain about 80-85% of original state. Keep from sulfating, keep water level up and maintain specific gravity. Oh and set charge rates correctly and use a “smart” charger.

Time to move on......

I was not intending to butt heads. I did though want to draw out of you the information about battery monitors, smart chargers and proper programming because as we see all the time on these forum's lots of folks don't have your knowledge and unless they hear otherwise will always buy the wrong battery and slowly destroy it with the factory installed converter.

[SR71 Jet Mech]

As I too see here quite often, especially in the solar,charger, battery and boondocking stuff which is why I try to offer some factual based knowledge. The more I’m challenged by the likes of you the more I learn.

As per your lithium battery charging, as with only being 100a mppt solar chargers at the top end, it would seem splitting the bank to charge and a disconnect to tie them together if the need arose to use all 600ah. Disconnect or split the bank in two either have one charger to charge one half at a time or two separate chargers.
This is my opinion just shooting from the hip, I would need to do some research but, where there’s a will there’s a way.

Every system in every coach needs extensive research. You can’t just run out to your electric meter and take the kWh per month and throw in a system. No matter what it is. That being said...if someone wants a 230ah bank and only 200w of solar, by all means have at it. If someone wants to charge at a 5%-10% rate then by all means have at it. Will these work? Probably, will they work well? Guess it doesn’t matter...

Mine does, so I’m happy.

No one ever said you can’t charge slower but it’s fruitless if you can’t charge your bank fully in a day....IMHO!

Maybe I should do this...

DISCLAIMER: this is only an opinion. No real research has been done by me on lithium battery charging in an RV. Boondocking situation with solar, inverter or converter. I will refrain from commenting further on lithium batteries and chargers.

Scott