high temp effects on battery lifespan

[bob g]

it has been suggested that perhaps another thread should be started
on the topic of how high temperatures effect battery life.

because of the unusually high summer temperatures witnessed by many folks across the globe this year, some of which depend on batteries for their energy storage needs, and based on everyones desire to get maximum lifespan out of those batteries i thought maybe a discussion was in order.

so here is a few links

http://www.apcmedia.com/salestools/SADE-5TNQZQ_R3_EN.pdf

while this link relates to ups systems which usually use vrla/gell/agm or some sort of sealed battery, the link also shows some data for flooded cells... apparently operating in ambient temperatures over 91 degree's F starts to have a toll on battery lifespans.  as temps go up 1 degree C (1.8F) the lifespan decreases by 2.5% per degree C.  it also relates to the increased need for watering under those conditions which ought to be seen as an indicator that maybe the bank is being operated at in elevated and deleterious manner, giving rise to the one maintaining the battery reason to investigate and take measures to alter the temperatures by whatever means are necessary even if it might mean discontinued use of the battery until temperatures can be lowered. (this if optimizing lifespan is of primary importance, and realizing of course this might not always be practical)

http://www.gillbatteries.com/pdfs/Flooded_Service_Manual.pdf

a bit more info in support of not operating at temperatures over 120F
and some info on increasing battery capacity at higher temperatures, higher levels of plate corrosion etc.

http://www.artec-ingenieria.com/pdf/guias_megger/New_BatteryTestingGuide_en_LR.pdf

page 16 Temperature, has the relevant info, operation of a battery bank in temperatures over 95 degree's F will cut the lifespan by half, 20 year batteries will become 10, 10 year batteries will become 5 year batteries..  this paper is actually excellent in my opinion on other facets of battery maintenance, charging, testing etc.
btw, at temperatures of 113 and above the 20 year battery can effectively become a 5 year battery... something to consider? i think so.

we can go on with research, however it would seem there is nothing to be said in favor of higher temperature operation of a battery, and much to dissuade one from doing so.

while the batteries are not operated continuously at elevated temperatures typically, it is not likely that the lifespans will be cut as dramatically as reported (provided everything else is in order) however the plate corrosion will be accelerated and this is not reversible

bottom line, if one has a significant investment in a battery bank or is anticipating such, he ought to seriously consider some means of temperature control for his battery room so as to not allow operation at elevated temperatures. maintaining room temperatures below 90 degree's F probably being a reasonable upper limit.

thoughts?

bob g

[ChrisOlson]

bottom line, if one has a significant investment in a battery bank or is anticipating such, he ought to seriously consider some means of temperature control for his battery room so as to not allow operation at elevated temperatures. maintaining room temperatures below 90 degree's F probably being a reasonable upper limit.

It might seem that some form of cooling might be necessary for hot weather.  But the reason I don't get too worried about it is that all these figures are given for sustained elevated temperatures.  Just because you get a couple weeks of hot weather at 100 degrees F does not mean the battery's life is automatically shortened to half.

It evens out where battery life is concerned over the course of a year if the batteries are well below their design 77° F for 9 months out of the year, right around their design temp for two months, and you get one month of hot weather where they'll be above.  I've seen starting batteries in various pieces of heavy equipment that live in 100+ degree heat for their entire lives and last 7+ years.

Going to the extreme of building a cooling system for batteries for an off-grid system certainly can't hurt anything.  And if you live in a hot climate it's probably desirable.  But concluding that such a thing is needed for once in a blue moon hot ambient conditions might lead you on a wild goose chase.
--
Chris

[Watt]

I believe I need to do a bit of research on car batteries and traction batteries to understand they are designed for different climates and environments in general.  Thanks for your efforts Bob, will look forward to this thread in the coming days and will only include the Climate aspect of my research. 

it has been suggested that perhaps another thread should be started
on the topic of how high temperatures effect battery life.

because of the unusually high summer temperatures witnessed by many folks across the globe this year, some of which depend on batteries for their energy storage needs, and based on everyones desire to get maximum lifespan out of those batteries i thought maybe a discussion was in order.

so here is a few links

http://www.apcmedia.com/salestools/SADE-5TNQZQ_R3_EN.pdf

while this link relates to ups systems which usually use vrla/gell/agm or some sort of sealed battery, the link also shows some data for flooded cells... apparently operating in ambient temperatures over 91 degree's F starts to have a toll on battery lifespans.  as temps go up 1 degree C (1.8F) the lifespan decreases by 2.5% per degree C.  it also relates to the increased need for watering under those conditions which ought to be seen as an indicator that maybe the bank is being operated at in elevated and deleterious manner, giving rise to the one maintaining the battery reason to investigate and take measures to alter the temperatures by whatever means are necessary even if it might mean discontinued use of the battery until temperatures can be lowered. (this if optimizing lifespan is of primary importance, and realizing of course this might not always be practical)

http://www.gillbatteries.com/pdfs/Flooded_Service_Manual.pdf

a bit more info in support of not operating at temperatures over 120F
and some info on increasing battery capacity at higher temperatures, higher levels of plate corrosion etc.

http://www.artec-ingenieria.com/pdf/guias_megger/New_BatteryTestingGuide_en_LR.pdf

page 16 Temperature, has the relevant info, operation of a battery bank in temperatures over 95 degree's F will cut the lifespan by half, 20 year batteries will become 10, 10 year batteries will become 5 year batteries..  this paper is actually excellent in my opinion on other facets of battery maintenance, charging, testing etc.
btw, at temperatures of 113 and above the 20 year battery can effectively become a 5 year battery... something to consider? i think so.

we can go on with research, however it would seem there is nothing to be said in favor of higher temperature operation of a battery, and much to dissuade one from doing so.

while the batteries are not operated continuously at elevated temperatures typically, it is not likely that the lifespans will be cut as dramatically as reported (provided everything else is in order) however the plate corrosion will be accelerated and this is not reversible

bottom line, if one has a significant investment in a battery bank or is anticipating such, he ought to seriously consider some means of temperature control for his battery room so as to not allow operation at elevated temperatures. maintaining room temperatures below 90 degree's F probably being a reasonable upper limit.

thoughts?

bob g

[bob g]

i am not sure, would have to do a bit more research but my bet is
automotive batteries because of their use in very hot underhood conditions have a lower specific gravity than a true deep cycle battery and are designed to handle the higher temperatures with the addition of calcium/antimony along with the more numerous thinner plates ability to dissipate heat more easily?
that and the fact that the alternators when hot taper the charge voltage way way back, often to as low as 13.8volts or even less.

as opposed to true deep cycle batteries having near pure lead plates, very thick which makes them harder to dissipate heat,  usually double wall cases which do a pretty good job of holding in heat, then consider the charging system likely is not going to taper back the voltage sufficiently because of the sensors placement is up and away from the core of the center batteries in the string.

gotta do a bit more reading to find out i guess

bob g

[ChrisOlson]

From my Rolls Multi-Cell Battery Manual appendix, Bulletin T2010-06:

Rolls/Surrette multiple cell renewable energy batteries differ from automotive/marine types in that automotive/marine cells are in a 2 x 3 layout and reside in a high temperature environment.  Renewable energy batteries have layouts of individual cells, 1 x 2 or 1 x 3 layouts.  Internal heat contained in the plates is always higher than case temperature.  Heat transfer (away from the plates into the acid and out of the battery case) is much better than in automotive/marine layouts or traction batteries with steel trays.  This means more aggressive charge regimes (higher bulk absorption settings) can be safely used in high ambient temperatures up to 50 deg C.

--
Chris

[ChrisOlson]

i am not sure, would have to do a bit more research but my bet is
automotive batteries because of their use in very hot underhood conditions have a lower specific gravity than a true deep cycle battery

Bob, I always thought it was the other way around.  The fully charged SG for our T12's is 1.250.

From the chart in the manual, the recommended absorb voltage is 30.0 from 0 - 16 degrees C.  28.8 from 17 - 40 degrees C.  28.32 above 40 degrees C.  Ending amps < 2% of ah capacity.

It says lower bulk absorption voltages at high ambient temperatures will require much longer charge times and result in higher water usage.

So the temp compensation in the Classic is pretty much dead on, and my batteries didn't do anything considered abnormal in the hot weather.

When in doubt RTFM.

Edit:  Not related, but I just came across another interesting thing in the manual that I had missed before:
Once every three months the bank should be discharged to the low voltage set point before starting the generator. This is usually dependent on the cut-off of the inverter which is usually 11 volts on a 12V system. The batteries are designed to be deeply cycled and a deeper discharge forces electrolyte deeper into the active plate material and helps open up fresh reaction sites.
--
Chris

[bob g]

Chris
can you provide a link to the manual?

particular interest to me is the specifications for your battery type, things like the lead chemistry, specific gravity, plate thickness, container design, that sort of thing

i can find all this for the common red case 4000 and 5000 series along with the 540 and the 460 series but can't seem to find much of anything on the t12 other than it appears to be a black case battery?

is this a fairly new offering from rolls/surrette?

thanks
bob g

[ChrisOlson]

I'm taking that from all the paperwork that came with the batteries.  I checked on Surrette's website and I don't see where they got the manuals for the different types and the bulletins that come out on them.  Under support they just got a generic downloadable manual (that I can find) that doesn't cover anywhere near what the 50 page one I got with the batteries has in it.

I think these batteries have been around for quite some time.  We had to special order them from the dealer though, as they weren't a normally stocked item.

They are lead/calcium low specific gravity batteries.  In the specs it says the plates are 254mm x 143mm x 4.32mm.  6 cells, 9 plates per cell, glass mat insulation, separator thickness 2 mm.  Capacity is 266 ah @ 100 hr rate, 252 ah @ 72 hr rate, and 200 ah @ 20 hr rate.

The dimensions are 38.44cm x 27.5 cm x 25 cm, wet weight 74.39 kg.

The container is polypropylene, 4000 series, and they got rope handles on them.  They are red case batteries.  The T12-250M is a black case marine version of it.
--
Chris

[thirteen]

I do not think my battereis will ever get over heated. The highest temp I get is 90 and a small creek runs 10 ft from the where the power house is being built. It stays nice and cool next to the creek. I am at 4000ft in the mountains. My problem is the cold from mid Oct to March. January hits   -20/-30 for about 40 days every other year 24 to 30 in of snow on the ground. Has anyone ever put there batteries in a spill container and then filled it with water for cooling and let it flow back to the creek. just asking

[Frank S]

I do not think my battereis will ever get over heated. The highest temp I get is 90 and a small creek runs 10 ft from the where the power house is being built. It stays nice and cool next to the creek. I am at 4000ft in the mountains. My problem is the cold from mid Oct to March. January hits   -20/-30 for about 40 days every other year 24 to 30 in of snow on the ground. Has anyone ever put there batteries in a spill container and then filled it with water for cooling and let it flow back to the creek. just asking

 I can see a possibility of an environmental issue in doing that unless this was to be a double boiler type of container that the water could not be exposed to even the air circulating over the batteries.
 For keeping batteries warm you could do like we did for our winter survival training course. wrap the batteries in a non conductive celluloid then keep them on an active charge rate. the insulation keeps the sharp cold air away from the cases and the charge keeps an internal flow of heat.

[ChrisOlson]

I can see a possibility of an environmental issue in doing that

If the DNR found out a person is diverting creek water and cooling batteries with it they would think up new fines never before seen in the history of man.

Our batteries are kept warm by having the utility room on the side of the house.  While the utility room is not heated and it can get down to zero in there, the batteries reside in insulated wood cases up against the house wall, and there is a small thermostatically controlled duct fan that pulls air from the kitchen and blows it into the battery cases.  They stay at around 60 degrees even at 30-40 below.

Keeping the batteries warm, for us, is way more important because if they get cold-soaked down to freezing their capacity is reduced quite a fair amount.
--
Chris

[thirteen]

My batteries will be in their own power house and with 6 in walls and also will have a fan that draws warm air from the house which is about 25 ft from the house. I was going to build it with foam blocks but I poured a footing about 12 foot long and I found out that during the winter and into the spring the footing raised on one end 1 in and cracked. The foot bridge that is just 8 ft from the footing also raised up on one side and stayed there so I had to shim the other side. At one time decades ago this was just a fill area for a log deck. I did not realize that until my nieghbor came by with his small back hoe and I had him dig down next to the footing and about 1 ft farther down he dug into just plain shale  type rock and you could see where it had been bushed, the cable buried was a good hint and you could also see where there are large boulders below but nothing between them.  So I am building my power shed 20 ft farther and in the end of my wood shed.  The ground is stable there and it will not change where my wiring will be going underground. The big thing is that the corner  of my house (living room , front door) is also on this fill area.

[ChrisOlson]

With your location I think you're more like us and keeping them warm is going to be more of a challenge than a couple weeks of hot weather in the summer and keeping them cool.  When they get down to 45 degrees or so you'll notice a definite reduction in ah capacity, and if they get down to freezing it's pretty drastic and can cause the generator to run excessively.

In the hot weather we had this past July I still didn't remove the insulation from the battery cases because it was 110 degrees in the utility room.  I put the duct fan on constant on so it was blowing house air into the battery cases, which was cooler than outside air but still around 90-95 degrees.  The exhaust air from the cases is vented to the outside to prevent fumes from getting to my inverters and other electrical equipment.  With the internal heat from charging they got nice and warm - I think I remember seeing the Classic saying they were at 117 degrees at one point.

I should've realized that checking water more often would've been the thing to do.  But I still find it hard to get overly alarmed that high temperatures for just a couple weeks out of the year is going to cause any drastic long term effects when the most of the rest of the year they run well below their design 77 degree operating temperature.
--
Chris

[bob g]

Chris,  i will concede that it is likely you won't have any long term issues with a couple weeks of hot weather, provided it doesn't occur with some frequency, and you keep the water levels up, reduce charge rate (which the controller is doing) and all that.

my point is and always will be however, if possible one should do whatever he can to keep them under 90 degree's or so or not use them during that period where cooling cannot be assured,,, however i realize that this is not always possible and even desirable for everyone.

so far i haven't found anything on the metallurgy and design of your batteries, but from what i gather so far it appears they were designed with a certain amount of owner abuse in mind,  the use of calcium generally supports this sort of scheme, it also lowers charging efficiency a bit, which leads to building more heat in some cases,,, depending on how much calcium is added.

btw, if you ever come across a link with the technical specs of your batteries i would be very interested in taking a look at that. 

i have a file about an inch thick on the other rolls/surrette batteries , with all the technical spec's of the various 5000 series batteries, so i am fairly familiar with how they should be used, handled and cared for.

just not at all familiar with the specific family of batteries you are using, i wonder if they have engineered them to work under a different set of criteria.

bob g

[ChrisOlson]

Bob, we don't have a scanner but we got a fax machine.  If I could figure out a way to fax my manual that came with the batteries to you I could do that.  The manual is in glued booklet form and I don't know how to get it thru the paper feed on the fax machine.  My wife might have a way she can do that.

I had not looked at Rolls' website for a long time.  It used to have a picture of a city on the homepage with a battery sitting in front of the city.  A set of jumper cables came out of the city and hooked up the battery, making the whole city light up and then a banner popped up that said, "Rolls - One Mean Battery".

There also used be a complete tech section on there with ALL their data and bulletins on it.

That has all been changed and it is totally different now.  I have an account with Rolls-Surrette and I logged in on it, then found out I need a ticket number to access anything.  It just said, "You have no active tickets - contact support".  Maybe they are still rebuilding their website and that stuff is coming back, because it used to be really nice.

When we got our batteries the dealer told us that for a high-amp system with the inverters we got, that they would be the best choice.  We could've gotten six volt Trojans for about 75% of the price of the Rolls, and they had a brand new pallet of Trojans in stock - and that's what I was going to get.  They talked me into these and it took better two weeks to get them.  The freight bill was horrendous - they came from out east someplace.

They later got 12 more T12-250's in at that same dealer and I was going to buy those and add them in too.  But then I thought better of it because we didn't (and still don't) have the charging capacity here for a 86 Kw bank.  Our bank is about 57 kW and that's a pretty good match to the wind and solar we got, and that's important too for proper maintenance of them.

I don't know a lot about the the types of plates they use - they give that by code for all their batteries, and our plate code is 250.  It says in the specs that that's a lead-calcium plate design with low specific gravity electrolyte - 1.250 normal for full charge @ 77 degrees F.  They got various other plate codes too, but it doesn't explain what they all mean, or what they're made of.
--
Chris

[bob g]

I noticed the change in Rolls/Surrette's website too, and i can't find any technical data on there anywhere,, hopefully it will return at some point.

they had a huge amount of very good info in years past available, maybe they got tired of having the content taken by others for commercial gain?

i don't know, but i do know i am interested in what they did different with the t12 batteries you have, different from the 5000 series?

talking to resellers about technical stuff often leaves one with less information than when he walked in the door.... its pretty bad when you have to educate the saleperson about what your needs are and what he has that would best fit those needs.. seriously some of these guys would sell you a group of 8d starting batteries for an offgrid solar house if you held still for it.

it often comes down to whatever they have in stock that has the highest profit margin for them or highest commission is the best thing since sliced bread! and if they don't stock it, it is crap!

bob g

[DamonHD]

Is this the right place:

http://rollsbattery.com/technical-resources.html

or here:

http://support.rollsbattery.com/solution/categories

I did have to enable JavaScript to get to those...

Rgds

Damon

[ChrisOlson]

they had a huge amount of very good info in years past available, maybe they got tired of having the content taken by others for commercial gain?

I'm thinking that what happened is that Surrette has been building high-end batteries for better than 50 years, and the Chinese manufacturers getting into the business they may have figured out that some of these Chinese manufacturers were gleaning information off their website.

Schneider Electric did somewhat the same thing with the Xantrex line of inverters.  You cannot get the technical information off their website anymore - only basic specs.  But if you call support and give them the serial number and model number off your product, they will send you a ticket number and email you a link that's good for 24 hours to download the data you requested.

Damon - no, those links are just very basic specs and generic information.  Rolls used to have a complete tech section with bulletins and everything on it.  It's all gone.

Another interesting thing I noticed is that they don't mention Surrette on the homepage anymore.  They now just call it "Rolls Battery Engineering".
--
Chris

[ChrisOlson]

so far i haven't found anything on the metallurgy and design of your batteries, but from what i gather so far it appears they were designed with a certain amount of owner abuse in mind,  the use of calcium generally supports this sort of scheme, it also lowers charging efficiency a bit, which leads to building more heat in some cases,,, depending on how much calcium is added.

Bob, another thing about these batteries is that knowing what I know now I don't think I would have gotten them.  They require more amp-hours during the high voltage stages of charging than other batteries I've seen.  Trojan also makes a 12 volt 6 cell RE battery that would be suitable for high-amperage inverter systems.  I don't remember the exact specs on it but IIRC it requires less voltage for absorb to get the same work done in charging the battery.

I just looked on Trojan's website and I can't find that damn thing on there either - but I know they make it.
--
Chris

[bob g]

Chris
i think you nailed it on the head when you mention the chinese concerns

not picking on chinese particularly, but in general it probably isn't a good idea to put out in the open market everything that gives you a market edge,, because there are those in competition that have folks on staff who's job it is to sit around and dig up every bit of technical info on the competition. 

you of all folks know this i am sure, my bet is cummins had folks doing this when you worked for them, just i am sure every other engine manufacture was doing the same.

couple that with this horrible global economy, and you have companies redoubling those efforts to gain market advantage. 

if the chinese build a quality deep cycle battery rolls is in trouble, because even with very high shipping prices the lower labor costs and government supported pricing  would allow them to deliver a similar battery for less money,,, and you know how the buyer is,  5% less might not be enough incentive, but 10% less? 15% less?  at some point
the chinese would have that market and we would lose a premier battery builder in this country and in canada.... once gone they likely could never return for epa reasons if nothing else... so...

i guess i am ok with rolls/surrette protecting themselves as best they can, make the competition work for it, no since delivering info right to their desktop.

this sort of thing has gotten so bad, and i have suspected it for some time now, that i decided to set a trap to see just how pervasive it really is...

on another forum i have a significant interest in  i published a research paper, and posted an abstract, then set the paper as a downloadable pdf file, however to download it you had to be a member... 
then being the admin and the one who has to approve new members i waited... doodley doo... tick tock

took less than 24 hours before i got applications from new members that had email addresses associated with oem's of generators. i approved them one at a time and watched where they went... they one by one would go directly to that download and take a copy.

now ordinarily i don't mind, "if" the new member goes on to be a contributor and offer some info in return that helps the group, on the other hand i take great exception to someone coming in and taking info and then continuing to lurk, offering nothing in return.

the funny thing was, there was really nothing new in the research paper that would be commercially viable, however from a DIY'ers standpoint the info contained was very useful.

what i learned from that is this, if i can lay out info as a little diy'er guy and attract attention of some oem's then it stands to reason that when folks like rolls/surrette (big guys) say or publish anything there is the equivalent of a huge sucking sound on the cable leading to the modem! 

kind of sad really because it stifles the free flow of information in my opinion.

bob g

[ChrisOlson]

Bob,

I found the info on that Trojan battery I mentioned!  It is called the J185H-AC
http://www.trojanbatteryre.com/PDF/datasheets/J185HAC_TrojanRE_Data_Sheets.pdf

If you read in there, Trojan actually has some useful information on battery temp vs life, and how it is affected over time.  It says:
While higher temperatures can provide improved discharge performance the increased rate of chemical reactions will result in a corresponding loss of battery life. As a rule of thumb, for every 10°C increase in temperature the reaction rate doubles. Thus, a month of operation at 35°C is equivalent in battery life to two months at 25°C.

OK, so why can't somebody make up a chart with this info in it?  Battery life is "rated" at 77 degrees F.  So if you have one month of the year when it's 100 degrees, three months at 75 degrees, two months at 50 degrees, and 6 months below freezing, how do those variations from 77 actually affect the "rated" life of the battery compared to if it had been held at 77 degrees for the entire 12 months?

I have never seen anybody provide that kind of information.

Or putting this another way - we had one terrible month of hot weather.  This is bad for the batteries.  But considering the cooler temperatures for the rest of the year, how much life from "rated" was removed by that one hot month, taking the whole year into account?  If there was some sort of tool to calculate this and that month of extremely hot weather does indeed reduce the life from "rated", or what is expected from the batteries at purchase, then a cooling system of some sort becomes something that a person should look at.
--
Chris

[bob g]

Chris

i remember rolls used to have just that sort of info on their site! it had all the graphs, calculations etc. so one knew straight up what the risk/rewards were when operating his batteries, cold---- hot and everywhere in between.

many years ago sandia labs also published a white paper, with excellent information that one could apply to a system so that you knew full well what the tradeoffs were.

i have most all of those white papers  and technical documents either in printed form or on various hard drives going back to the later half of the '90's.  having just relocated across the country a year ago, being caught up in a huge remodel project, garden and all the other crap, i just  now am starting to sort though boxes of stuff... so far i have found a bunch of rolls battery technical spec's like we were talking about, but haven't come across the sandia labs papers and the tech bulletins from rolls that relate to these and other issues with offgrid use of batteries.

soon as i can relocate some of this info, and/or locate it again online, i will be forwarding it to the forums, as i believe everyone should have a copy of the materials.

its maddening to know that this stuff used to be widely available on the net, and maybe it is still there?  all i know is what was once very easy front page available on google, either is no longer available or is way the hell down the page count making it very hard to locate again.

this confirms my belief that when info is available, even if it doesn't seem to be useful right then, one ought to go ahead and download a copy or at least let others know of its availability so that it might be preserved in the forums archives or as least we know someone who has a copy.

that is why we have a "white papers" board on our forum, someplace to store pdf files, links and other information.. every now and then i prod the members to remind them to keep an eye out for anything and everything that might be useful and to post it there... which reminds me
i am past due prodding the membership!

bob g

[ChrisOlson]

i remember rolls used to have just that sort of info on their site! it had all the graphs, calculations etc. so one knew straight up what the risk/rewards were when operating his batteries, cold---- hot and everywhere in between.

Damn.  That information is NOT in my battery manual that I got with the batteries.  All it says in relation to temperature and life is what I posted a few posts back.  And it seems they ain't really too worried below 125 degrees (at least not with the multi-cell batteries).  Having that info would be cool (pardun the pun).

It's kind of interesting looking at the big Trojan 6 cell vs the Rolls, the Trojan uses an automotive style layout for the cells (judging by the cap locations).  Rolls uses a longitudinal layout in their big 12V - which I assume is what they are talking about with the heat dissipation of the thing.
--
Chris

[Frank S]

I don't think this site has much of the older data sheets but you can download lots of sheets pertaining to different DC power batteries

http://www.dcpower-systems.com/downloads_data_sheets.aspx
 it has a couple on the Rolls and several on the trogans  the concordes and a couple others , as well as sheets on charge controllers combiners, Inverters and other stuff
 well worth looking into

[Volvo farmer]

I copied this off Rolls website before it disappeared.

http://www.frontier.net/~bobwenn/anotherp0wer/Rolls%20Surrette%20charging.pdf

I'll leave the link active for the next little while, but it was some pretty nifty information for off grid battery users.  Information like this is why I chose Rolls for my first bank.

Hoops like I had to jump through with support tickets, etc when my batteries began to fail left a bad taste in my mouth and I chose a different manufacturer.

[ChrisOlson]

I copied this off Rolls website before it disappeared.

I'm a little unhappy about that.  I'm half tempted to think up a problem with one of my batteries and call support to get a ticket number to see if it gains me access to all those bulletins that used be on their website.  Then download em all and save em.
--
Chris

[Frank S]

Chris use the fact that one of your batteries used more water than the others and it took quite a while to get it back in balance during the 2 week hot spell
that way it is not a lie that you would have to try and remember LOL

[ChrisOlson]

I doubt it would work.  They'll just look up my information in their system and go, "you bought your batteries from an authorized dealer only 35 miles away from you.  Why are you calling us?"

"Ahhhh.........well...........I want one of them ticket numbers to see what I can download off your website."

LOL!  I have a good idea how far that would go.
--
Chris

[thirteen]

explain that the price of gas is to high to just drive 75 miles and ask a few questions.