Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

nowayout

Longtime Lurker/First time poster here. I want to reach out to the gurus here on battery choices.
I am upgrading the battery bank in my 40' class A diesel RV and am considering a couple different Trojan batteries. Here are the specs:

System Specs

Motorhome - Class A diesel pusher
System Voltage: 12 Volts
Inverter/Charger: Magnum MS2812 with BMK and auto gen start (125 amp max charge rate)
Generator: Onan 8000 watts
Solar Panels: None yet (future)

Available Physical Space

My current battery bay is a side door. The space is 36" wide x 13" deep (front to back) and 32" tall. It is large enough to accommodate 8 T105 or 4 L16 series 6 volt batteries.
The Magnum inverter is in a bay just to the right of the battery bank (close for wiring)

Battery Considerations

1) I want to install as many AH as my space and current charging capability will allow.

The MS2812 has a max charge rate of 125 amp.
At Trojans recommended charge rate of 10%-13% of 20hr ah bank capacity, that is a 960ah - 1250ah bank. (125a max charge rate /10% - 13% = 960ah -1250ah)

2) I could fit 8 Trojan T105's in the space. This would be the least expensive option, but would result in 4 parallel strings (2 6v batteries in series x 4 strings) which is not recommended.

The alternative is to go to L16 /903BCI size series. I can fix 4 comfortably in my battery bay, which would be 2 parallel strings.

This selection of which L16 is where I am stymied and can't decide which would be best.

3) Trojan offer many L16 variants, from the "entry level" AC series L16E-AC to the "Signature Line" L16P & L16H and also the "Premium Line" L16RE-B.

The differences seems to be small, although there is some difference in weight and AH ratings.

http://www.trojanbattery.com/pdf/TRJN0111_ProdSpecGuide.pdf

4) I have narrowed it down to the following:

Qty

Series

Capacity Each (20hr-rate)

Bank capacity (20hr-rate)

Weight Each

AH capacity @20% DOD

AH capacity @50% DOD

Life Cycles at 50%DOD

4

L16P - (datasheet)

420ah

840ah

114lbs

168

420

1200

4

L16H - (datasheet)

435ah

870ah

125lbs

174

435

1200

4

L16RE-B (datasheet)

370ah

740ah

118lbs

148

370

1700

5) Cost. The price difference isn't great. The L16RE-B is about $60 (my price) more than the L16P. Not enough to worry about.

6) The one main difference is the L16RE-B has their newest "Smart carbon" technology, but at a reduced AH rating. In theory I should be able to get more cycles out of it, but I doubt I would ever reach that point in a motorhome environment. It is not used full-time and is stored for at least 4 - 5 months every winter (although I can control the storage conditions)

7) Questions:

• Why does Trojan offer 2 batteries so close in specs - L16P & L16H (only 15ah and 11 lbs difference)?
• Knowing that I probably wouldn't ever realize the increased cycles out of the L16RE-B, should I just take advantage of the increased AH rating of the L16H or L16P?
• Are there functional differences in time to charge or other differences between the AV and the Signature Line - RE?
• Are there any other good choices that would achieve an ~800ah bank?
• What am I missing?

I appreciate any/all comments. It isn't often that you get the chance to upgrade battery banks and I want to do it right.

Thanks!

mike95490

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Thats a lot of battery bank. There are 4v and 2v batteries,
http://www.solar-electric.com/trl111ah2dec.html
that can be used to increase Ah without going to parallel strings. (Some, like i linked to, have a 3 cell case with the cells in parallel, so your watering task gets WORSE.)

nowayout

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

mike95490 wrote: »

Thats a lot of battery bank. There are 4v and 2v batteries,
http://www.solar-electric.com/trl111ah2dec.html
that can be used to increase Ah without going to parallel strings. (Some, like i linked to, have a 3 cell case with the cells in parallel, so your watering task gets WORSE.)

Many large diesel pusher Coaches have large battery banks, usually AGM since the owners want a maintenance free install. I don't want to go to AGM's, would rather put that same money to flooded lead acid by adding capacity or quality.

Here is a pic of the battery bay.

Attachment not found.

Don't mind the cables, they will be redone with the new batteries. The Coach had 2 8D batteries with dry cells that an old Xantrex inverter had fried.
So for now I have installed 4 Deka 8C6V 330ah batteries from a seldom used scrubber at my work for a week or two until I get permanent batteries. So my bank now is about 660ah. They are a few years old and aren't in super good shape since the charger at work does not have any equalize function and the SG varies a bit from cell to cell. I have done an equalize and it helped, but still not at 100%.

2 volt won't work very well since I would need 6 batteries and my space won't accommodate that easily. I looked for 4 volt industrial batteries, but didn't find many sizes that would let me put 3 of them in.

If I want to stay to one string, I could use 2 6 volt batteries with higher AH ratings or a single 12 volt battery.

In the Trojan Industrial line I could fit 2 of the IND9-6V series http://www.trojanbattery.com/pdf/datasheets/IND9-6V_TrojanRE_Data_Sheets.pdf
Trojan says they are designed for 1500 cycles @ 80% DOD.

At 80% DOD and a 464ah bank, I could get 371ah capacity.

That is very similar to the 4 L16RE-B bank at 50% DOD, but the cost is roughly $250 more for the bank.

So is a single string bank of 2 IND9-6V at 80% DOD better than a 2 string bank of L16RE-B @ 50% DOD? Is it enough to justify $250?
How much value should I place on getting to s single string?

One other choice is to go to a single 12v battery, maybe a Crown industrial 530ah

http://www.solar-electric.com/crinba6.html

My last question is, am I Ok in using 50% DOD on the Trojan non industrial line, and 80% DOD on the Trojan Industrial and Crown line?

One point is that I need to have these installed in the next 20 days, so need to make sure something is in stock.

Thanks!

vtmaps

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

nowayout wrote: »

2 volt won't work very well since I would need 6 batteries and my space won't accommodate that easily.

Welcome to the forum,

Check out Deka's 2 volt batteries... I think they will fit.

If you do buy an industrial battery that can handle 80% DOD, you should be prepared to recharge it all the way to 100% immediately. These batteries are usually charged from the grid (unlimited time and energy). Industrial batteries also tend to take longer to recharge... not a problem if you're on the grid. Finally, make sure the batteries can handle the vibration.... some industrial batteries are meant to be stationary, and have pure lead or lead calcium plates which confer some advantages at the expense of being less rugged.

--vtMaps

Dave Angelini

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

vtmaps wrote: »

Welcome to the forum,

Check out Deka's 2 volt batteries... I think they will fit.

If you do buy an industrial battery that can handle 80% DOD, you should be prepared to recharge it all the way to 100% immediately. These batteries are usually charged from the grid (unlimited time and energy). Industrial batteries also tend to take longer to recharge... not a problem if you're on the grid. Finally, make sure the batteries can handle the vibration.... some industrial batteries are meant to be stationary, and have pure lead or lead calcium plates which confer some advantages at the expense of being less rugged.

--vtMaps

Also make sure you have the required ventilation for flooded batteries. You should have airspace around the individual battery if you are headed for the warm/hot places like Mexico. I would wait on the new model Trojan especially as vtmaps posted about vibration! Let someone else do the early testing.

nowayout

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Dave Angelini wrote: »

Also make sure you have the required ventilation for flooded batteries. You should have airspace around the individual battery if you are headed for the warm/hot places like Mexico. I would wait on the new model Trojan especially as vtmaps posted about vibration! Let someone else do the early testing.

Fortunately the battery bay is well ventilated. How much space is recommended between the individual batteries? In my picture above I realized when i was done I didn't leave any space. I will have a permanent fastening method for the new batteries and was planning on leaving 1/2". I have noticed though that floor scrubber batteries rarely have space between nor do forklift batteries.

When you say new Trojan, are you referring to the RE series that now has the Smart Carbon? I believe the RE has been out for a few years and they just added the Smart Carbon technology. I don't really have a choice in that I need to purchase something in the next couple weeks. I am current researching forklift batteries and the 2 volt Deka's that vtMaps talked about. I think they will fit but at quite a high price over the other options.

Thanks for the comments!

zoneblue

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

You are overlooking the obvious solution with the L16s. Increase your system voltage to 24V. One string, less controllers, less wire, less amps, less loss. Get a inexpensive 24v-12V converter for whatever 12v gear you have, and bobs your uncle. Once you get solar you wont regret it.

nowayout

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

zoneblue wrote: »

You are overlooking the obvious solution with the L16s. Increase your system voltage to 24V. One string, less controllers, less wire, less amps, less loss. Get a inexpensive 24v-12V converter for whatever 12v gear you have, and bobs your uncle. Once you get solar you wont regret it.

I did actually consider this, but only for a moment as it just isn't possible with this particular coach. The systems are so tightly integrated that you would have a very hard time converting to 24v. For example, all of the lighting is 12v (fluorescent, LED and Halogen). The heat exchanger and furnace blower motors are all 12v. The onboard computer systems that monitor the engine control, the leveling system, interior safety system and monitoring are all 12v. Some of these come from the 12v chassis battery while others come from the house bank. Since large diesel engines are notoriously difficult to start when cold (and hard on batteries) there is built in boost system with heavy duty solenoids to provide 12v to the engine starter if needed. The 12v alternator is heavy duty and provides charging to the house bank when driving. It is a tightly integrated system and would be very difficult (and very expensive) to convert to 24v. I do realize there would be some inefficiencies, but I doubt they would overcome the headache and costs, I don't think I would attempt this.

It is a 2006 Country Coach Allure - cost $465,000 new currently value is about 175k. Some pics of a similar model here: Pics - Country Coach 2006 Allure with tag axle

I know that one string is ideal and reduces problems, but are the issues and headaches going to be significant moving from 1 string of 2 6v batteries (or 6 2 volt batteries) to 2 strings of 2 6 volt batteries each (4 total 6v batteries)? I may be naive, but I struggle with justifying a huge expenditure to just to get to one string (or to 24v from 12v). If this was a standalone PV system in a home, I would certainly go 24v or even 48v since there wouldn't be an existing 12v infrastructure I had to mesh to.

I have done some research on the MK/Deka 2v solar batteries, but the information on them is very scarce, even on their own web site. They have marketing brochures, but I had a hard time even finding dimensions and specs. I have sent tham an email but no reply.

I do like the idea of going to an industrial battery that is designed around an 80% DOD, even at a higher cost. There are several Crown banks that would fit. GB battery also has similar sizes and availability. It seems that GB rates their forklift batteries with a 6hr rate and allows you to use all of that AH without de-rarting to 80% DOD. Is this common with forklift batteries? http://gbindustrialbattery.com/Battery_Options/AH_Ratings.html

Thanks!

Blackcherry04

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

You can buy Industrial / Forklift batteries about any size you want. The smallest cells are 16 " high and about 6x6" , you can buy them cased from one cell to as many as you want. The heights are the variable 16, 20, 25 ,28" The are sold in amp hr capacity and the number of plate pairs per cell.

The cheaper than Industrial batteries is to buy Surrette / Rolls S-1400 EX it's a 2 v 1000 amp hr in a L-16 case. It has 1/4 " forklift plates and has ample room for the electrolyte ( forklift batteries don't ) . Don't know if you have enough room to work 6 in. The next best would be S-1725, same size and 1380 amp hr @ 2v. ^ Batteries your looking at $2,800.

How about having someone weld you a custom rack where you could double stack GC-2 golf carts and slide the racks in and out for service ? 8 @ 6v 220 amp hr, 880 amp hr , 580 lb and less than $800. They are predictable, that alone means a lot with batteries. They have less voltage sag @ 12 V and a whole lot easier to charge.

www.rollsbattery.com/public/specsheets/S-1400EX.pdf‎

www.rollsbattery.com/public/specsheets/spec_36.pdf‎
.

Vic

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Seems that with these Coaches, that as long as a dying battery bank does not leave one stranded, if one gets 15 - 18 months from the House Bank, things should be fine. Such a low standard as this makes many things considerably easier. Stationary off-gridders mostly want 10 -15 years from their banks (I do, at least).

OOooooppppssssss, attitude & Opinion, Vic

nowayout

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Vic wrote: »

Seems that with these Coaches, that as long as a dying battery bank does not leave one stranded, if one gets 15 - 18 months from the House Bank, things should be fine. Such a low standard as this makes many things considerably easier. Stationary off-gridders mostly want 10 -15 years from their banks (I do, at least).

OOooooppppssssss, attitude & Opinion, Vic

For the most part, I would agree, but not all. There are a few reasons why. First the vast majority of the service, battery mods and replacements occur at the hand of an RV dealer. Have you ever had the misfortune of dealing with an RV dealer? :-) I avoid it like the plague!

The second reason is that many (not all) owners of RV's and high end coaches are at a point in their lives where they want luxury, and they want it easy and carefree and they are willing (and able) to pay for it. This means they don't want to check water levels, SG or SOC. They have no desire to set absorb, float or equalize values or times to match their battery bank. They rely on the dealer to do this (and you know how that goes). They want to push a button and be done. Now you link this up with the RV dealer and you have a match made in heaven! We know what the RV dealer sells and installs...what he makes the most money on!

The last reason is that many Coaches/RV's do not include the very best equipment when it comes to components. Unfortunately the lowest bidder of an component wins rather than the best match to the other components. It seems the vast majority of RV Inverter/Chargers fry their battery banks into oblivion. When it burns the battery bank dry, the RV dealer installs an expensive set of "maintenance free" AGM's, forgets (or doesn't know how) to properly set the charger levels, and everyone goes on their way...for another 15-18 months (like you mentioned). Rinse and repeat.

I am not the norm, not old nor rich, never visited an RV dealer for service or sales, and my installation may as well be my home, it just so happens to have wheels! :-) I do my own maintenance and upgrades and love to understand the where, why and how a system works. It is pure joy to see a system with parts working in harmony.

I was forced to upgrade my charger/inverter almost a year ago, just after I bought the coach. My crappy xantrex burnt out. At that time I didn't have the knowledge I have now. I put in the Magnum MS2812 with BMK and AGS, which has been a great inverter and is supposedly a decent charger. Probably not the best, but hopefully enough settings to not jeopardize the other components. I probably wish now I had purchased an Outback inverter and added a stand alone charger. Time will tell.

Your perspective is dead on...for the majority of the RV industry. There is a reason though I am reaching out to this group rather than RV'ers. :-)

mike95490

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

How do you resolve the voltage of the starting battery, with the house batteries, with the house batteries needing a different charge regime than the starter ?

nowayout

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Blackcherry04 wrote: »

You can buy Industrial / Forklift batteries about any size you want. The smallest cells are 16 " high and about 6x6" , you can buy them cased from one cell to as many as you want. The heights are the variable 16, 20, 25 ,28" The are sold in amp hr capacity and the number of plate pairs per cell.

The cheaper than Industrial batteries is to buy Surrette / Rolls S-1400 EX it's a 2 v 1000 amp hr in a L-16 case. It has 1/4 " forklift plates and has ample room for the electrolyte ( forklift batteries don't ) . Don't know if you have enough room to work 6 in. The next best would be S-1725, same size and 1380 amp hr @ 2v. ^ Batteries your looking at $2,800.

How about having someone weld you a custom rack where you could double stack GC-2 golf carts and slide the racks in and out for service ? 8 @ 6v 220 amp hr, 880 amp hr , 580 lb and less than $800. They are predictable, that alone means a lot with batteries. They have less voltage sag @ 12 V and a whole lot easier to charge.

www.rollsbattery.com/public/specsheets/S-1400EX.pdf‎

www.rollsbattery.com/public/specsheets/spec_36.pdf‎
.

Good ideas! My initial choice was T105's. I can fit 8 in the space, but I am looking at 4 strings. That is a whole bunch of cabling, 24 caps to remove to check SG and while it is priced right at around $800, I don't think I can talk myself into it. Plus not many recommendations on 4 strings.

I can't fit 6 L16 2v into the space. :-( I have exactly 32" of width. This is when I realized that 4 L16RE-B 6v would be a good solution. 2 strings of 2. I can get these for a killer price of $315 each, $1260 for the bank of 4.

I also like the IND9-6V which is part of Trojans Industrial design. 2 of them would be 1 string, 464ah capacity with 370ah use-able at 80% DOD (which is supported by Trojan and still has 1500 cycles). Should be around $1500-$1600 for the pair and total weight is only 420lbs. This is my current best choice.

http://www.trojanbattery.com/pdf/datasheets/IND9-6V_TrojanRE_Data_Sheets.pdf


I like the forklift battery concept, but am having difficulty finding specs - sizes and ratings. GB shows combined banks, but no individual cells. Same with Crown and Deka. Maybe I will call a few tomorrow.

GB info is here. http://gbindustrialbattery.com/Forklift_Battery_Sizes_and_Specifications_Zone15.html

Almost any of their 12v banks would work.
6-75-13 - 709ah - 530 lbs and $1309 list
6-100-13 - 946ah - 612 lbs - $1558 list.

Seems like a decent choice.

nowayout

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

mike95490 wrote: »

How do you resolve the voltage of the starting battery, with the house batteries, with the house batteries needing a different charge regime than the starter ?

They solve it by using an Intellitec isolater relay, which works but is far from ideal as far as the best charging practices for my prized battery bank.

http://www.intellitec.com/assets/pdf/1453-intellitec-pdf-template-53-01000-000.pdf

As far as I know, you can't control the rate or voltage of the alternator through this relay...this is going to be a problem.

Ideally I would like a charge controller that would accept 12v input from the alternator or 120v from shore power or genset, but still honor all the charge parameters and settings. Does such a controller exist? Would a solar charger/combiner work?

The 2 chassis batteries (sealed maintenance free SLI's) are charged with a small controller when stationary on grid shore power (or genset). It is essentially a trickle charger.

zoneblue

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

As you say those kind of relays often yeild poor results, unless the house bank is right next to the alternator, and the wires are fat, and the charge setpoints are vaguely compatible. Better than nothing i suppose. More sophisticated house bank chargers usually have some sort of voltage boost circuitry.

vtmaps

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

nowayout wrote: »

As far as I know, you can't control the rate or voltage of the alternator through this relay...this is going to be a problem.

Ideally I would like a charge controller that would accept 12v input from the alternator or 120v from shore power or genset, but still honor all the charge parameters and settings. Does such a controller exist?

I don't know if it exists...but i suggest you turn to the marine market for your research... I notice that Victron makes a variety of chargers that are designed to charge two battery banks.

--vtMaps

Blackcherry04

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Here is a company that manufactures all kinds of of relays and battery solutions, converters for the Marine market.

http://sterling-power-usa.com/prolatch-r-160amp12vor24v.aspx

Blackcherry04

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

nowayout wrote: »

I like the forklift battery concept, but am having difficulty finding specs - sizes and ratings. GB shows combined banks, but no individual cells. Same with Crown and Deka. Maybe I will call a few tomorrow.

GB info is here. http://gbindustrialbattery.com/Forklift_Battery_Sizes_and_Specifications_Zone15.html

Almost any of their 12v banks would work.
6-75-13 - 709ah - 530 lbs and $1309 list
6-100-13 - 946ah - 612 lbs - $1558 list.

Seems like a decent choice.

Enersys General Batteries are the series that can be ordered any size you want. Under that series they have 4-5 different battery construction and sizes of cells. GB batteries are the Sams Club of the forklift battery world, don't confuse GB with General Batteries two different companies with two different products with names that can confuse.

http://www.enersys.com/Lead_Acid_-_Flooded.aspx
.

stephendv

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

These guys also do a split charger: http://www.smartgauge.co.uk/smartbank.html

nowayout

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

vtmaps wrote: »

Welcome to the forum. Check out Deka's 2 volt batteries... I think they will fit.
--vtMaps

Blackcherry04 wrote: »

You can buy Industrial / Forklift batteries about any size you want. The smallest cells are 16 " high and about 6x6" , you can buy them cased from one cell to as many as you want. The heights are the variable 16, 20, 25 ,28" The are sold in amp hr capacity and the number of plate pairs per cell..

Well I finally found some good specs on the 2 volts cell that both of you mentioned. Deka's website has zip, they referred me to their division MK, but the guy was out. I did find some very good specs at BBI Battery. They had great specs and dimension on both all the 2 volt cell options as well as assembled units. This document finally made it clear to me how the 2 volt cells work, their sizes and capacities.
BBI 2 Volt Cell specs

I can see now that you can configure just about any physical size bank you want...very cool! It baffles me that Crown, MK and GB don't publish the same thing, it is obvious from their numbering scheme and limited info that they are using the same 2 cell specs.

I did talk to GB on their 12v assembled units (6 2v cells).
http://gbindustrialbattery.com/Forklift_Battery_Sizes_and_Specifications_Zone15.html
6-75-13 709ah $1285
6-85-13 804ah $1385
6-100-13 946ah $1481

They did have some refurb units with a 1 year warranty at about 60% of the above new costs, but with shipping they came out just a few $$$ less than new, so not worth it.
All are available with a 3 day build time and free shipping on the new units. Knowing I can reliably use these to 80% DOD, these seem like very good prices!

So maybe someone can chime in on these questions:

1) Are there many differences amongst the forklift companies that make 2v cells? So far I know of Crown, MK (Deka) GB Industrial and BBI (who has the best info by far!)
Is their technology similar? Who would be your first choice?

2) Does the number of plates per 2v cell make a difference? Am I better off with more or less...or doesn't it matter? It looks like a 21 plate 55A size (x6) will work good for my space.

I'm liking the forklift battery direction. I still have to verify the vibration/ruggedness issue that vtmaps brought up.

Thanks for the great info!

nowayout

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Blackcherry04 wrote: »

Here is a company that manufactures all kinds of of relays and battery solutions, converters for the Marine market.

http://sterling-power-usa.com/prolatch-r-160amp12vor24v.aspx

Nice find! But correct me if I am wrong...wouldn't this isolator/switcher merely select which bank would charge when (under a preset condition?)

My main concern with the alternator charging my new bank is not knowing (or being able to control) what it does to it, no ability to control any parameters. While on shore power or genset my Magnum would charge it with my specific presets for bulk, absorb float etc, then I would hit the road and the alternator would charge differently. I did find this advanced alternator regulator on the same site - it allows for 4 step charging.
Sterling Advanced Alternator Regulator
Now if I can customize its settings to match my Magnum, then I should be set. I may need to use it in conjunction with the Prolatch.

Are my concerns warranted about the alternator charging my forklift bank in a completely different fashion than my Magnum? I don't want to make things overly complex.

My other choice is to not allow the alternator to ever charge the forklift bank. I could use it to the designed DOD and then run the genset to charge it as needed. The reality is that many times the genset is already running to enable the rooftop AC's to be used while traveling..especially in Summer. This may be a better plan...and not too complex.

Thanks!

zoneblue

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Like i said its more likely that the alternator wont be able to charge much due to a) lower setpoints, and b) cable losses. Check the alternator output, newer ones do have higher setpoints, but they still tend to err on the side of under charging. SO it will "contribute" during bulk. Then use your other sources to do the absorb and eq. If you really want more control over the alternator you will need a charger than boosts the voltage and has 3 stage smarts. But remember that the wisdom of doing any of that depends on how far and often drive. I always found that we never spent enough time on the road to do much damage, hence thats where solar comes in.

vtmaps

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

nowayout wrote: »

1) Are there many differences amongst the forklift companies that make 2v cells? So far I know of Crown, MK (Deka) GB Industrial and BBI (who has the best info by far!)
Is their technology similar? Who would be your first choice?

2) Does the number of plates per 2v cell make a difference? Am I better off with more or less...or doesn't it matter? It looks like a 21 plate 55A size (x6) will work good for my space.

I'm liking the forklift battery direction. I still have to verify the vibration/ruggedness issue that vtmaps brought up.

If they are meant for use in a forklift, they are rugged. I notice that BBI makes an 'alternative energy' battery. I don't know the difference between that battery and their forklift batteries... it may be that the alternative energy battery is meant to be stationary.

Some batteries have thicker plates and therefore more lead than thinner plate batteries. Other batteries have thicker, but fewer plates, so they have the same amount of lead as a battery with more, but thinner plates.

Thicker plates means longer life and/or deeper discharges. The current you can draw from a battery is a function of the surface area of the plates. A battery with fewer, thicker plates can supply fewer amps for a longer time. They also take longer to recharge.

One thing that worries me about your plans is the 80% discharge. The forklift batteries are typically drawn down to 20% SOC in an 8 hour shift, and then immediately recharged to 100%. They do not spend a lot of time at low SOC. If it takes you a couple of days to get down to 20% SOC, and then a few days to get back to 100%, you are NOT treating them as they are intended to be treated. As mentioned, it takes a long time to charge a forklift battery... will you be able to do that frequently?

Also, forklift batteries do not have PSOC type use (PSOC= partial state of charge). In a system such as yours (and most solar powered systems) it is typical to partially discharge and partially charge a battery. This causes stratification. Each discharge and partial charge cycle 'ratchets up' the stratifiction. The taller the battery, the more of a problem stratification becomes. The only way to break up the stratification is to 'overcharge' the batteries which causes gassing which stirs up the electrolyte. A forklift battery is charged to the gassing point every day.

--vtMaps

Blackcherry04

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

There is so much to understand about batteries and their construction and design use, charge and discharge cycles. Most fork lift batteries are of a true single cell construction ( one set of plates and posts ). Surrette's 2 V are two sets of plates in a common pool of electrolyte with one cap. The cells are tied externally to the post. Trojan does / did theirs differently, theirs is 3 cells and everything is separate and tied internally. One could assume that they make them so they will fit a Industry standard case size or they do it to be able to be able to transfer a certain amp capacity. Voltage sag is a problem with forklift batteries. A Inverters efficiency takes a huge nose dive as you drop below the nominal design voltage. So if you plan to go the 80% dod you should consider the voltage issue. In a forklift it really doesn't matter, in our world it does.

vtmaps

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Blackcherry04 wrote: »

T Trojan does / did theirs differently, theirs is 3 cells and everything is separate and tied internally.

Trojan also makes a true single cell 2 volt battery in their industrial line.
http://www.trojanbattery.com/battery/industrial-line-flooded/2v/

--vtMaps

Blackcherry04

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

vtmaps wrote: »

Trojan also makes a true single cell 2 volt battery in their industrial line.
http://www.trojanbattery.com/battery/industrial-line-flooded/2v/

--vtMaps

Yes they do in that model, Even on their data sheet they do not show how or if it's one cell or more interconnected in common electrolyte pool , not that i think it makes a difference. Trojan is very respected in the battery world, so I'd say they know their stuff. There must be something to do with Amp Hr capacity that causes them to make them that way.

nowayout

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Blackcherry04 wrote: »

Yes they do in that model, Even on their data sheet they do not show how or if it's one cell or more interconnected in common electrolyte pool , not that i think it makes a difference. Trojan is very respected in the battery world, so I'd say they know their stuff. There must be something to do with Amp Hr capacity that causes them to make them that way.

I looked at their 2 cell industrial, the problem is their limited sizes. They only offer two size and both are HUGE AH. I can't fit 6 of them in, my bank would be 6' long and I would have to put it in a trailer! :-)

What about using the 6volt version in the same industrial line? It would be one string at either 495ah or 695ah (if I could fit 2 of the IND13-6v)

They do advertise 80% DOD in their industrial line. http://www.trojanbattery.com/products/deep-cycle-flooded/industrial-line-flooded/
I guess the difference that vtMaps is referring to is they specifically indicate they address PSOC in their design, which could apply to me, although I think I could address it.

I realize that the forklift batteries are designed around a 8hr discharge/charge cycle to 80% DOD. This is obviously to cover 8 hours of work in a warehouse. The reality though is that many forklifts are not used continuously and may take 2 or 3 days to reach 80% DOD, at which point they are charged. They do sit idle at various SOC. We use 2 Crown forklifts in this exact manner and haven't seen any battery issues. One is at 7 years and the other at 5 years and both are still at near full capacity. Both have watering systems on them.

In my use I would probably not reach 80% DOD in one continuous cycle, it may span a couple of days, or at times would be one day. Since I am not relying on solar, I could charge them as soon as they reach 20% SOC with the genset and could charge to 100% in one cycle (not span days).

I am going to confirm this use with BBI and get the info on the Alt E differences (if any)

nowayout

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Blackcherry04 wrote: »

There is so much to understand about batteries and their construction and design use, charge and discharge cycles. Most fork lift batteries are of a true single cell construction ( one set of plates and posts ). Surrette's 2 V are two sets of plates in a common pool of electrolyte with one cap. The cells are tied externally to the post. Trojan does / did theirs differently, theirs is 3 cells and everything is separate and tied internally. One could assume that they make them so they will fit a Industry standard case size or they do it to be able to be able to transfer a certain amp capacity. Voltage sag is a problem with forklift batteries. A Inverters efficiency takes a huge nose dive as you drop below the nominal design voltage. So if you plan to go the 80% dod you should consider the voltage issue. In a forklift it really doesn't matter, in our world it does.

Good point. Lets see if I am understanding correctly what you are saying. At 80% DOD, the forklift battery cutoff voltage is 1.75apc or 10.5 volts for my 12 volt bank. My Magnum inverter will continue to invert but will be less efficient since it now has to invert 10.5vdc to 120vac instead of the normal 12-14v, correct?

The Trojan Industrial line also shows the same cutoff at 20% SOC, so the issue is the same as with forklift batteries, correct? I guess it is not as much an issue if one stays at 20% or 50% DOD since the voltage at those levels is much higher than 10.5v.

In my use case I like the 80%DOD since it lets me carry an overall smaller bank and still have roughly the same AH capacity. I understand I may be giving up some life cycles.

Blackcherry04

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

nowayout wrote: »

Good point. Lets see if I am understanding correctly what you are saying. At 80% DOD, the forklift battery cutoff voltage is 1.75apc or 10.5 volts for my 12 volt bank. My Magnum inverter will continue to invert but will be less efficient since it now has to invert 10.5vdc to 120vac instead of the normal 12-14v, correct?

The Trojan Industrial line also shows the same cutoff at 20% SOC, so the issue is the same as with forklift batteries, correct? I guess it is not as much an issue if one stays at 20% or 50% DOD since the voltage at those levels is much higher than 10.5v.

In my use case I like the 80%DOD since it lets me carry an overall smaller bank and still have roughly the same AH capacity. I understand I may be giving up some life cycles.

Not exactly, you are talking about 10.5 volts unloaded. With any load on the Inverter you'd be lucky to have 9 volts, way below a inverters low voltage cut off. Once you get into the 11.5 range you cannot count having any sustained load on them.

Yes, on the efficiency of the inverter because your getting out of it's conversion range. The way around the drop is to move to a higher voltage, even then the voltage sag will be a problem.

feedhorn

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Blackcherry04 wrote: »

The way around the drop is to move to a higher voltage, even then the voltage sag will be a problem.

I got around the drop in voltage by going to Lithium Iron battery. Its flat discharge/recharge curve gives me almost a full 1 volt higher operating voltage. This keeps my LED lighting much brighter than it was with lead acid batteries. I can also recharge this battery completely in one hour if it gets low.

Vic

Re: Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

Just to try to extend some things stated previously;

Forklift batteries DO generally have fewer, thicker plates, compared to common Deep Cycle batteries. This does reduce the peak current available, and means that they have poor voltage regulation (as noted by vtmaps, and blackcherry04). This can be a significant disadvantage for RE systems, particularly when running A/Cs, refers, and some pumps etc. This also often causes lights to dim/flicker during the surge of motor-starting. Believe that the Trojan Ind series batteries would behave in this fashion.

Regarding the desire to be able to typically cycle the House bank to 20% SOC, this is probably, generally a not-so-good idea, for the reasons stated earlier, AND also because the impedance of Lead-Acid batteries increases significantly at each end of the charge/discharge curve. This yields, even poorer voltage regulation below (perhaps) 40-ish percent SOC. This is not a linear function, but can easily be seen during discharge cycles (where it matters most).

BTW, Surrette makes several sizes of two and four volt batteries in their 5000 series. these batteries use 1.265 SG electrolyte vs 1.280 for many of those being discussed in this thread. This lower SG is beneficial in RE applications, generally.

FWIW, opinions, Vic