Trojan L16xxx vs L16RE-B - RV Replacement Battery bank

nowayout

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

Blackcherry04 wrote: »

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.

I couldn't find an efficiency curve for my magnum inverter, but isn't the issue also the battery's ability to deliver the same load at lower voltages? I realize that a constant load will require higher dc amps as the voltage drops. That is pure math (amps*volts=watts) but also due to Peukert's law on the battery and the inverter efficiency curve, correct?

So if I was drawing a constant 500 watts, that is ~43 amps @13vdc (assuming 90% inverter efficiency) but at 10.5vdc, it might be 64 amps, (75% inverter efficiency). Is this roughly correct? (although not exact numbers). So the time from 12 volts to 10.5 volts isn't going to be very long, right?

Is this more of an issue with forklift batteries as opposed to the Trojan industrial line..or does it occur with any lead acid battery?

I ran across this interesting thread...this guy Chris Olson seems to know what he is talking about. He is a fan of the Surette 5000 series. Isn't this similar to the Trojan Industrial line? He doesn't dislike forklift batteries, just talks realistic about them.

http://www.permies.com/t/29241/solar/deep-cycle-batteries-brand-solar

westbranch

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

One thing to keep in the abck of your mind about Chris's setup is that IIRC he has 3 custom turbines and PV to generate a whole whack of power, so he can charge his batteries at HIGH rates if needed. Heavy (deep) discharge levels needs High recharge rates

nowayout

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

Vic wrote: »

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 the being discussed in this thread. This lower SG is beneficial in RE applications.

FWIW, opinions, Vic

Thanks Vic, I referenced that thread from another forum that likes the Surrette 5000 series as well before I saw your post. You sure there isn't a sublimal Surrette message going on? :-)

So the Trojan Industrial line will not behave like the Surrette 5000 series?

I talked to BBI Battery today regarding their 2 volt cells. They only make one version, nothing specific for the RE industry. They will do a custom build with any of their 2v cells in virtually any configuration - 1x6, 2x3, 1x3 etc. Seems like a very good option....IF I decide to go the forklift direction. Hmmm...

nowayout

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

westbranch wrote: »

One thing to keep in the abck of your mind about Chris's setup is that IIRC he has 3 custom turbines and PV to generate a whole whack of power, so he can charge his batteries at HIGH rates if needed. Heavy (deep) discharge levels needs High recharge rates

Yes he does, plus 2 generators (gas and diesel). I guess I was intrigued at his take on forklift batteries vs Surrettes and his pros/cons.

BBI Battery recommended a max charge rate of 16.3-20 amps per 100ah, so C/16.3 to C/20, but said that a lower rate such as C/10 or C/15 would be fine, albeit with a longer charge time.

My Magnum MS2812 has a max charge rate of 125ADC which requires 18AAC (120V). My genset is plenty large to deliver that rate, so I am good there. I know I won't be able to rely on the alternator to charge to completion. And there is always shore power!

Cariboocoot

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

No.

Stop.

You guys are going into the realm of craziness.

Every battery has a power curve regardless of type, Voltage, or capacity. That curve is how fast the Voltage drops under a given, fixed draw. From this Amp hour capacity @ 'X' hour rate is determined, using the quite-unlikely-in-the-real-world constant current demand. The curve is just that: a curve. It is not linear. The lower the battery goes the faster it goes down. For a fixed Watt output it's a nasty exponent because the current goes up as the Voltage goes down which means the 'real' capacity at any given moment is less than at the start because of the above capacity determination being based on a fixed current.

Do you know why there's so many 'similar' batteries from the same maker with only slight variations? Because there's 100,000 forklifts, floor scrubbers, or golf carts which they are designed to work with. None of them, no matter what the makers say, are design to work with RE applications because no two RE applications are alike. It's easy to design the best battery for 100,000 of a known load, especially when that load is constant and you have all the mains power you need to recharge it perfectly.

We are all of us using less-than-ideal batteries for our systems. No company can make one that works well everywhere. This is why you have two people with the same battery getting different degrees of satisfaction.

The design of the plates does have a bearing on things, despite what some so-called experts say. Thick plates are used in deep cycle batteries in order to last a large number of cycles. In the same size case you may put in 'sponge-like' plates in order to give high current ability for starting a car. You try for both and you get a battery that doesn't work very well for either. But there's a lot you can get away with. So you have people giving anecdotal evidence of how automotive batteries work fine in off-grid applications and two-bit diesel mechanics spouting off as though they have electrical engineering degrees. Listen to the Internet long enough and you'll hear every lie told as truth.

Avoid Industrial batteries for RE. They usually require higher Voltages than are easily obtainable from PV systems and ridiculously long Absorb times. Always find out what the recommended charging regime is for any battery you are considering before you buy it. Frankly I avoid both Trojan and Surrette due to their higher-than-normal Voltage requirements, price, and in Surrette's case rather poor quality and customer service.

Over and over we recommend getting cheap to start with so you'll learn not only about how RE systems work but how your particular one works without blowing a lot of money. Over and over I tell people to get the right equipment for the job and repeatedly they don't and then wonder why it doesn't work.

I don't know. I guess the message is don't waste years in university, just go to a 2 year mech-tech course and made lots of money servicing junk 'cause people only listen to the rich, not to the knowledgeable.

Vic

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

Hi nowayout,

Personally, have run Surrette 5000s for almost nine years. Have had very good luck with them, and at this point would buy them again if the need arose.

Sometimes believe that people make a bit too much about Stratification. If the SG returns to the target value after an Absorb, (and the electrolyte is close to normal fill level spec), then there cannot be much/any stratification.

Chris Olsen's situation is atypical. He has a significant wind resource, so some of the things that he does with his system, and recommends on occasion, are from the perspective of having almost grid-like power, due to the wind's contribution an night or even 24-ish hours at times (at least). He does seem to be a smart chap.

It can be difficult to select batteries, and there seem to be more opinions on which to select than there are persons being asked. It is not simple, BUT, things do not need to be perfect, and seldom are they. Only need to be perfectly acceptable.

One thing about Industrial style batteries, is that there is often a significant "Reserve Volume" of electrolyte -- the space for electrolyte. The Surrette 4KS25s in use here (5000 series), have 3.75 inches of this reserve electrolyte above the plates. The Trojans may well have something similar. This could be somewhat important for your situation, if it is difficult to get access to and view the electrolyte level when the batteries are in their compartment.

Yet more opinions ... Vic

nowayout

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

Cariboocoot wrote: »

No.

Stop.

You guys are going into the realm of craziness.

Avoid Industrial batteries for RE. They usually require higher Voltages than are easily obtainable from PV systems and ridiculously long Absorb times. Always find out what the recommended charging regime is for any battery you are considering before you buy it. Frankly I avoid both Trojan and Surrette due to their higher-than-normal Voltage requirements, price, and in Surrette's case rather poor quality and customer service.

Over and over we recommend getting cheap to start with so you'll learn not only about how RE systems work but how your particular one works without blowing a lot of money. Over and over I tell people to get the right equipment for the job and repeatedly they don't and then wonder why it doesn't work.

Crazy? I had to be or I wouldn't have purchased the motorhome!

Thanks for the reality check. My use case is slightly different from most here in that I don't have PV and don't need to rely on it for my charging needs. I also rely frequently on shore power or genset. I came here because you are 1)technical, 2)know batteries, chargers and controllers, and 3)this forum is VERY active and seems to have a low BS factor. As such I appreciate all the frank comments.

So on batteries...you say to avoid Industrial batteries for RE, also avoid Trojan and Surrette. I don't dispute your rationale, but what is your recommendation then?

Cariboocoot

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

nowayout wrote: »

So on batteries...you say to avoid Industrial batteries for RE, also avoid Trojan and Surrette. I don't dispute your rationale, but what is your recommendation then?

What I personally have used with good results are Crown and East Penn/Deka/US Battery (3 names, all the same company really). Others on the forum have had good results with even the cheapest GC2's. The reason is the recommended charge Voltages for Absorb are in the 'normal' flooded cell range, i.e. less than 2.48 Volts per cell. When you need to push up to 2.5 Volts per cell as part of the standard charge regime it can become difficult to achieve in a typical day.

Some of the people running Surrettes have gone through quite a bit of aggravation, having to apply very high Voltages for very long times to get the 'commissioned' and then having to do regular 'corrective' EQ cycles at even higher Voltages to keep the cells in line on SG. Rather a pain to do, frankly.

Your having shore power and/or gen for charging gives you a big advantage in that department; all you need is a charger that can be programmed to the right Voltage/time. That, btw, is how most of these batteries are meant to be recharged. When you haven't got that to work from you can run out of sunlight before you get to Absorb Voltage, much less through that stage. And you can't just turn the Amps up ever higher to charge faster or you may end up cooking the battery.

Quite a difference between having 24 hours unlimited power to charge with and having a 4 hour bell curve.

vtmaps

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

nowayout wrote: »

So the time from 12 volts to 10.5 volts isn't going to be very long, right?

Is this more of an issue with forklift batteries as opposed to the Trojan industrial line..or does it occur with any lead acid battery?

The rate at which you can draw down a battery is a function of the surface area of the plates. If thicker plates means fewer plates, then the battery's ability to sustain large current draws will be limited. But thicker plates can mean longer life and deeper discharges.

The main caveat about industrial batteries, in my opinion is, as I mentioned earlier, that they take a long time to charge. Cariboocoot wrote: "They usually require higher Voltages than are easily obtainable from PV systems and ridiculously long Absorb times". Not a problem if you are on the grid, but they may require long hours of generator use. One reason you have batteries is so that you don't have to run the generator all the time.

And yes, the charging voltages are high enough to interfere with some DC loads.

nowayout wrote: »

I ran across this interesting thread...this guy Chris Olson seems to know what he is talking about. He is a fan of the Surette 5000 series. Isn't this similar to the Trojan Industrial line? He doesn't dislike forklift batteries, just talks realistic about them.

Re Chris Olson, he does know what he is talking about, but in my opinion he enjoys battery maintenance too much. He has a six strings of those batteries in parallel. That is generally considered poor design. In order to make it work, he periodically disassembles the bank and load tests each battery and then reassembles them. This way he can try to rearrange them as need to try and keep the strings balanced. He has admitted, in at least a couple of forums, that his next battery will be a high capacity forklift battery.

--vtMaps

Vic

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

Cariboocoot wrote: »

No.

Stop.

You guys are going into the realm of craziness.


The design of the plates does have a bearing on things, despite what some so-called experts say. Thick plates are used in deep cycle batteries in order to

Avoid Industrial batteries for RE. They usually require higher Voltages than are easily obtainable from PV systems and ridiculously long Absorb times. Always find out what the recommended charging regime is for any battery you are considering before you buy it. Frankly I avoid both Trojan and Surrette due to their higher-than-normal Voltage requirements, price, and in Surrette's case rather poor quality and customer service.
.

Hi Marc,

I really hate to argue ... however I will say that MY direct experience with the Surrette battery banks here, and those of a couple of neighbors simply DO NOT NEED EXCESSIVE, or even high Absorption voltages, at all, period. We have been Absorbing at 58.2 (2.425 V/cell) for the past number of months, Winter setting. In the Summer run in the high 57s.

There were those two folks, one running Surrette T-12275 (or similar number) in four strings. He SAID that these batteries had Lead-Calcium plates, which is a very different animal, if correct. Lead Calcium is often chosen to reduce/eliminate gassing for little or no maintenance. These were not Ind batts, but he said that he was running 64 V Absorb. And then there was that one person here, who was running Trojan IND-something in a 48 V bank. He, also, said that he needed to run close to 64 V for Absorb ... these are the only two incidents that I remember HERE regarding high Vabs.

Why am I nagging on this ?? Because, there seems to be a lack of data to support this high Vabs report with Surrettes, or in general for Industrial Trojans. And, when a Moderator says something, people pay attention to it. You Mods have very high credibility, for good reason. And, if one forms an opinion about something like this, then it is often becomes gospel.

Some high Vabs situations arise from batteries with high SG electrolyte. Certainly many Trojans use 1.277/1.280 SG electrolyte, and forklift batteries use this, or even higher SG electrolyte. These batteries need higher Vabs for this reason if no other. The Surrettes, in general, use 1.265 (1.250 for Loco starting batts, IIRC).

The above are my opinions, but, at least they benefit from actual experience with Surrette S-530 (L-16s), and 4KS25s (5000 series), over a period of a number of years. AND, as stated before, the few neighbors near us, running Surrettes, report very similar numbers for Absorption voltage. The only exceptions have been for opportunity charging -- trying to jam in as much charge as possible on short Solar days, and in my case of cycling the bank to 50-ish percent SOC, the Vabs really needs to be about 58.4 or 58.5 V in the Winter. The full recharge, in this case, just finishes on the second day at the previously noted Vabs.

Just my experience with Surrettes. Tedious, pedantic Vic

Cariboocoot

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

No, Vic; that's good. Your Voltages are normal indeed.

But you know what? So many people have had problems with Surrettes and even the company told them to turn up the Voltage. Now if anyone can explain why the lower Voltage is right for 'model X' for some people but the higher Voltage is right for 'model X' for others I'd love to hear a logical explanation.

I suspect it is a dreadful inconsistency in the make up of the batteries. I have not seen similar discrepancies in qualification among other brands, including Trojan (which are meant for higher charging Voltage according to their own specs).

It also makes me wonder if some of those batteries are being filled with the wrong electrolyte solution depending on where they are built or other random factors. I know Wayne got some made in 'his backyard' and is happy with them.

The only other explanation that comes to mind is inaccuracy in the Voltage readings at the site itself, which would be quite the nightmare to try and verify.

My opinions are formed from reading all the posts and distilling all the information therein and then trying to make a rational analysis of it. From that I see more dissatisfaction with Surrettes than satisfaction, and the Voltage issue (as well as other inconsistencies with the brand) tops the list of complaints.

Search for posts about various battery brands and you will find complaints on Surrette, and Trojan. You will not find complaints about any other brands, and I know people use other brands. You will find complimentary remarks on other brands, and on Surrette and Trojan.

Again we are all at the mercy of none of them being ideal but some being better than others, and that will also depend on which battery gets put in to which system. It's just shy of going to Vegas and rolling the dice. That is why it's best to start out with the cheapest you can get, just in case something isn't right. Besides which you may get 5 years out of them anyway. Unfortunately the cheapest are not available in all sizes, so if you have to spend the big money double check everything including what sort of mess you will be in should your choice fail prematurely.

Side note: some retail brands such as Interstate have different models made by different companies, so one might be 'known brand' and another my be 'generic' leading to potential variations in quality between models in the same company.

vtmaps

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

Cariboocoot wrote: »

You will not find complaints about any other brands, and I know people use other brands.

Huh? I've read your complaints about Interstate. --vtMaps

Cariboocoot

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

vtmaps wrote: »

Huh? I've read your complaints about Interstate. --vtMaps

Yes but I complain about everything, so it doesn't count.

When you get to be a grumpy old man you'll understand that.

Vic

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

Marc,

First, many of us have recommended that those with chronically undercharged battery banks (Surrette and others) CRANK UP Absorb time, and often crank up the Vabs, especially in Winter months, I know that I have done so. Would expect that the manufacturer would do the same -- little to lose in taking these actions.

There are always variations (inconsistencies) in exactly how each cell/battery happens to be manufactured, and so on. You make a good point about Surrette & Trojan, vs the other manufacturers. But, one important piece of data missing from the Reports of Trouble from these manufacturers, is the sales volume and installed base of batteries from each of these manufacturers. Also missing is data concerning the source of these banks ... Dealer, Distributor, Direct sales relationship, and the effect that this might have on the quality of the battery that is delivered to the ultimate customer.

One additional thought, concerns the apparent fact that there are not that many manufacturers of batteries serving North America. But these few manufacturers brand batteries with many different labels, either as Contract suppliers or for different divisions or channels within one company. This might dilute the number of trouble reports for any given "name".

And one further comment on batteries with very thick plates (and not such a large number of them) -- Forklift. probably Trojan IND, and perhaps Scrubber batteries (?). These batteries with fewer, thicker plates, in my opinion, do not have as much surface area to foster generous agitation during Absorption at any reasonable voltage. So, perhaps high Vabs is required to really mix the electrolyte.

None of the Surrette battery banks here have really thick plates. They are medium thickness 4KS25s have a 0.270" thick Positive plate, IIRC. If the above is true, then, this might be one reason that these (and the general) Surrettes do NOT require high absorption voltages, unless one is attempting Opportunity Charging.

Just opinions, will look some more for plate thickness specs on some of the Trojan batts, etc
.
AND, I cannot fathom the number of hours that Cariboocoot Marc, and BB Bill spend moderating this very, very active Forum. Just look at the number of people visiting this site at any one time -- many, many, many hundreds - this must be a lot of work !! Thank You very much!
And while am at it. Thanks again Wind-Sun for this great resource in the Forum, and your excellent business practices, service and very reasonable prices you folks offer. And so on, Vic

Blackcherry04

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

A day in the life of a bank of Surrettes. 2 V, bank of 6, S-1725's, 1300 amp hr's . I started the day at 5:00 this morning to pull them to 50 % and do a complete recharge, SG's 1.230 @ 13.5 V floating. I put a 50-100 amp load on them and by 12:00 I had them to 11.7 volts and a SG of 1.195. I started a re-charge @ 135 amps and they spent 2 hrs in bulk and went to absorb @ 14.9 v for about 2 hrs with a ending amps of 4 amps and they went to float. I checked the SG level, 1.205 , .025 less than where I started.

I started a EQ for 4 hours @ 15.0 V at the end of 4 hours the SG had climbed to 1.220. I am now on my second EQ after 2 more hours I am now @ 1.230, after 10 hours of charging I am back right where I started.

Guarantee you this my last set of them. They are just not predictable, If I didn't have a Gird connection, I'd be up the creek.

Vic

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

Bc04,

At times I have seen wide variation of SG readings on a single cell, on successive samples. This has always been on a partially charged battery.

One other point, Surrette recommends a minimum EQ voltage of 15.48 volts for a 12 v flooded battery. They have been emphatic, in the past that this is a MINIMUM voltage (and of course needs to be temperature compensated). Possibly your reference to a 15.0 V EQ voltage is just a typo.

Too bad that these Surrettes are not living up to your expectations. You do have a lot of experience whipping batteries into shape. Hope that these will respond ... more later. Good Luck, Vic

nowayout

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

...with no paddle...err, power. Dang that sucks. How old are they?

Well Surrettes were never on my shortlist, thanks for the warning though.

I talked to BBI Battery today to get their production timeframe. Found out a couple interesting things. The 85amp plates are most of what they stock and can configure and ship in a few days. Most of the other plates are special order - 3 weeks or so (45,55,75,100 and 125 amp)

They don't sell direct, so have to send me to a local fork lift dealer. I found out that they produce all the cells for GB battery. Later I talked to GB to get some pricing and they confirmed it. Maybe this is common knowledge and shouldn't surprise me. They did confirm that Crown made their own cells as did Deka/MK. Interestingly enough, they preferred Deka to Crown, saying that Crown never went back to the better technology that C&D has before they started outsourcing a line to Mexico.

I'm going to order the BBI 2v cells on Monday. Trojan is the runner up. I don't want Surrette and I can't seem to get info out of Deka/MK, they wont call me back, hardly any info on their website. Crown is the outlier, never talked to them.

I appreciate all your expertise and comments!

Blackcherry04

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

How old are they?

October 2013, factory direct to me. they were commissioned right away and been on float and were Equalized in February.

One other point, Surrette recommends a minimum EQ voltage of 15.48 volts for a 12 v flooded battery. They have been emphatic, in the past that this is a MINIMUM voltage (and of course needs to be temperature compensated). Possibly your reference to a 15.0 V EQ voltage is just a typo.

Good catch, it was 15.5 V, the ambient was 75° at cell level.

I checked most cells and moved around the bank to see if one just was lagging. This morning they are about 1.240 and I have them back on equalize this morning. I'll see how it goes.

Blackcherry04

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

Nowayout, I settled for the Surrette's but had searched on a custom forklift battery. The plate amperage determines the height of the cell ( 55 amp plate is 15" high, etc ) The number of plates determines the footprint size. ( from 9-33 plates ) with 6" x 6" the smallest as I recall.

Good Luck with them, hope it's better than my experience so far. Mine will come up, it's just what I have to do to get and keep them up. It's just way more effort than necessary.

Cariboocoot

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

So far I haven't had to EQ the East Penn batteries I use. The cell SG has been very consistent across them all. And they charge at 28.8 Volts.

No matter how 'identical' a company tries to make each battery there can always be variations. This is one of the reasons we caution against mixing old and new even of the same type.

Blackcherry04

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

Cariboocoot wrote: »

So far I haven't had to EQ the East Penn batteries I use. The cell SG has been very consistent across them all. And they charge at 28.8 Volts.

No matter how 'identical' a company tries to make each battery there can always be variations. This is one of the reasons we caution against mixing old and new even of the same type.

Yours react more like GC-2's and are predictable. There has to be something in the alloy of these plates that make them react the way they do. What I am seeing is a Partial Plate Recharge. When I Equalized them in February the outcome was the same, a normal discharge and recharge. The only problem is that it is the charging source is reacting to the voltage and amperage going into the battery and how it reacts. The SG 's were low and were all over the place battery to battery. I used a power supply and brought the SG's of each up to the same level. Here I am a month later right back in the same place. The SG's were low when I started (1.230 ) they had been on float for a month, not alarming. Now a month later It's right back.

I just don't know if time, voltage or Ending Amps means anything with them, it has to be SG level and huge amounts of charging time.

Cariboocoot

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

Blackcherry04 wrote: »

Yours react more like GC-2's and are predictable. There has to be something in the alloy of these plates that make them react the way they do. What I am seeing is a Partial Plate Recharge. When I Equalized them in February the outcome was the same, a normal discharge and recharge. The only problem is that it is the charging source is reacting to the voltage and amperage going into the battery and how it reacts. The SG 's were low and were all over the place battery to battery. I used a power supply and brought the SG's of each up to the same level. Here I am a month later right back in the same place. The SG's were low when I started (1.230 ) they had been on float for a month, not alarming. Now a month later It's right back.
.

Why do I think this behaviour is related to the need for constant-current charging which is common to most batteries of this type? Which of course is not an option with solar.

Into guesswork now so I'll stop.

Blackcherry04

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

Cariboocoot wrote: »

Why do I think this behaviour is related to the need for constant-current charging which is common to most batteries of this type? Which of course is not an option with solar.

Into guesswork now so I'll stop.

And or Stratification. The only issue with that is it takes a much higher voltage and time than a normal recharge to deal with. Once I go above 16 V I lose the inverter on High Voltage cutout.

Cariboocoot

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

Blackcherry04 wrote: »

And or Stratification. The only issue with that is it takes a much higher voltage and time than a normal recharge to deal with. Once I go above 16 V I lose the inverter on High Voltage cutout.

This is often a problem on 12 Volt systems and another reason to avoid them if possible. But they can't always be avoided and you can't always choose an inverter that can take the higher Voltage and you can't always put a couple of diodes in to move the inverter Voltage down 1 and so you'd better beware of batteries that may need such high Voltage.

If only it were as simple as having every component interchangeable between every system. Ha, ha, ha. :roll:

Vic

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

Speaking of guessing ... bc04,

Looks like you started the cycle-to 50% discharge when the bank was at about 75% SOC. If the bank had spent some time at this SOC, then perhaps Stratification has contributed to the low and varying SGs.

One added thing; have found that when using the HydroVolt Hydrometer, I can see wide SG readings on a partially charged battery. It is possible that I was not filling the chamber fully. This one HV (the only one of those that is in use), the scale can stick, and needs a bit of a rap to get it to read on the scale at all ... Usually use the reliable old Freas most of the time. The HV is sure easy to read (and not to rag on the HydroVolt too much).

//end guessing for now I guess. Good Luck with those Surrettes. I floated one of the Surrette banks here on Solar for far too long. This was not the best thing for it. As you do know FLAs do like and need to be cycled (as you were obviously doing). Vic

Vic

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

AND, bc04,

One of the other things that am having trouble understanding about the termination of the first charge after you cycled this band to about 50% SOC, is the very, very low EA value -- 4A -- at that relatively high Absorb voltage. Even with grid power to allow the Absorb to continue for ten or twelve hours, doubt that either of the similar sized Surrette banks here woulr EVER end Absorb via EA, with the lower relative Absorb V of 14.55V/12 V bank. Here, 1350 AH Surrettes (really 1280 AH at the shipped 1.265 SG electrolyte) EA at 11.9 A at 14.55 relative V.

Would guess that your bank cycled to 50% SOC might want over five or so hours of Absorb. But the EQ sure should have finished a normal charge from 50%.

Coot, we EQ the banks here about every 4-ish months, for about one hour. Did need to extend it to two hours once, when a FW update changed Temp/voltage comp limits for a Classic. Previous version applied NO limits on this, and when WX turned cold, was not around to notice that there was NO temp comp of Absorb.

Believe your batts need fewer EQs because they are cycled deeper more often than those here ... cycling is a good thing!

Merry Spring. It has clicked over to Summer weather here. Vic

Cariboocoot

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

Vic wrote: »

Believe your batts need fewer EQs because they are cycled deeper more often than those here ... cycling is a good thing!

This is true, and is one of the reason I don't recommend the big "many days of autonomy" banks; most of the time they wouldn't get cycled very deep!

Merry Spring. It has clicked over to Summer weather here. Vic

Ha, ha. It's 25F here today. Might snow.

Blackcherry04

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

Just to let you know, I am there 1.265 across the board. It took 20 1/2 hours. I am really going to examine how they got this way considering that I had them on float ( 13.6v ) and I had equalized in mid February. I will agree with Vic at 1.230 they were sulfated and 75% charged.

mike95490

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

If these batteries are going in an RV, and it hits the road 1x a week, the cells should be jostled around enough, to keep the electrolyte from stratifying, IMHO.

nowayout

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

mike95490 wrote: »

If these batteries are going in an RV, and it hits the road 1x a week, the cells should be jostled around enough, to keep the electrolyte from stratifying, IMHO.

Yes they will get jostled around, we never stay in one place for too long when we are out. Now to be fair, we are not full-timers, so they will not be used constantly. There will be periods where we don't go out for weeks. It is stored indoors with shore power, so I can control the conditions. It is also stored over the winter from about mid November to mid March. but I have full access to it so can cycle the batteries as needed. I will have to come up with a good regimen for when it is stored.