BB. wrote: »
Do any of you guys have Battery Monitors (or equvalent) to measure the current and Amp*Hours you are running through the batteries during charging/loading?
If you have parallel strings, is the wiring all equal length and tight connections? Have you used a DC amp meter to ensure that all strings are properly sharing the current?
maok wrote: »
today I noticed, that my wirings isnt tight enough. when charging, it was big diference in the voltage on the charger /13,6V/ and on the batery terminals /13,18V/.
so now I am charging, so we will see... thanks.
niel wrote: »
gee, i thought the fla types were more forgiving and easier to deal with and the multiple threads showing up on surrettes seem to show a possible flaw in that thinking, at least for the surrettes anyway.
are there any other fla types having this much trouble?
hillbilly wrote: »
I've seriously considered going with a sealed battery to replace the current set of surrettes I have, not so much in the hopes that I'd have better luck with them as much as just the fact that I wouldn't be able to worry over them as much.
mbzebro wrote: »
To get an idea about the state of indivual cells without SG readings I took loads of voltage readings of all cells at different charge/load currents and SOC. You get a lot of data to obsess and worry, believe me.
With sealed batteries you can additionally worry about individual cells that go to high voltages on absorb (I had some going up to 2.60V), because they would lose electrolyte thru gasing and could eventually dry because you cant add water (which didnt happen).
One thing I liked about my AGMs was low internal resistance and low peukert coefficient making them noticeably more efficient than my surrettes (are low peukert and low internal resistance necessarily linked?)
Another advantage of AGMs is that being obsessive about them doesnt leave holes from sulfuric acid on clothes (my partner has found quite a few of them lately)
tennyson wrote: »
Though all the batteries were at 5.2V at the end of the test, Surrette warranty said they would only replace the 1 battery that had dropped to 3.5V, claiming that single battery had somehow compromised the capacity of the other batteries. I pointed out that even if the 3.5V battery were 5.2V, the whole string would still be well under 42V which is their definition of a full state of discharge. At 180 ah, the capacity of the other batteries was well below their spec of 400 ah (20 hours rate, so it would be a bit less at 37A which is roughly the 10 hour rate).
I'm going to see if the local distributor I picked up the batteries from will replace them. I'm an EE with access to test equipment so I could easily determine when they were dispensing the happy horseshit. But, I could only imagine the confusion they would sow with a layperson along with the endless time one would expend trying to get them to honor their warranty.
trkarl wrote: »
I called Surrette again and had a long conversation with a tech named Serge. His email is [email protected]. He was very helpful. I found that the date codes on the three batteries were different than the other ones. But it was only off by about 8 months so no big deal. He said that they were probably dry stored and then activated when i ordered them. He said that to dry store them they fill them with electrolyte and fully charge them then remove the electrolyte and wash them out and maybe not all the acid was washed off the plates on those batteries with the high sg. That is what I was told.
Cariboocoot wrote: »
I have had similar experience years ago, albeit with a different brand. That one battery can go bad and cause damage to the others isn't BS. That they should use that as an excuse to not warrant all affected batteries in a single application is.
In my case it was three in series on a 36 Volt (yes) system. Two went bad, and the dealer wouldn't replace them saying they were properly charged. The fact that this is impossible in a series install didn't sway him. I've never bought anything from them again, and have recommended to everyone around here to stay far clear of them.
This is why I regard warranties as an unreliable measure of a product's quality; you can warrant anything for anything, but if no one stands behind it a warranty is just a piece of paper full of words made up by weasily lawyers to absolve the manufacturer/retailer of any responsibility. I prefer to rely on the real-world experiences people have had, which includes the results of what happens if they screw up - an important 'acid test' of both product and seller.
So does Surrette make good batteries? Or just expensive ones? Might as well buy from Costco, after hearing the positive responses from those who have!
Solar Guppy wrote: »
37 amps, is closer to the 8 hour rate, fully charged ( 1.265 SP GR ) is speced for 320ah. Was your SP GR made at 25C? if not you have to compensate for temperature.
What did you use for a load? only an electronic load tester could provide constant current, a load through an inverter would be constant power and as the voltage drops the current would increase.
Having weak cells will effect the test, make charging full near impossible and on discharge when the cell become near dead will drop not proportional to the remaining cells capacity
mbzebro wrote: »
There are charts of DOD vs cycle life where you can see that Surrette is referring to 50% DOD cycles. When only discharging to 10% or 20% DOD daily, many more cycles can be expected (approximately linear to 50% DOD/real DOD ratio), according to these charts.
One thing I just noted is that Surrette replaced the spec sheets of the S4000 series. Where before capacity was given for 1.265 SG now I see only 1.280 SG; the capacity should be 5% higher for the 1.280 SG, but it reads the same.
When I searched for spec sheets for the 6CS17 I found older ones with 1.265 and newer ones with 1.280 SG, with other specifications like capacity being equal.
The labels of me 6CS17 all say 1.265 SG, but all my cells show 1.280-1.290 SG.
If they changed electrolyte SG from 1.265 to 1.280 they should tell their customers.
Solar Guppy wrote: »
There is a 20% difference in amps pulling at 40V vs 48V ... so that would probably push you close to 45 amps towards the end of the test. Inverters for this reason are not a good method to verify ah capacity. Looking at the chart, you would be closer to 300ah , not 400ah you posted
I also would be some what suspect on the accuracy of the T80, for sure its not going to report within 1%, if your going to challenge the manufacture, you should probably use a 50amp , 100mv shunt and a DVM ( voltage across the shunt ) to verify the current draw, I'm assuming your using a 500amp/50mv shunt which is 5% typical shunt tolerance and further effect your ah calculations.
Hopefully, when you get the two bad cells replaced, you will get much closer to expected performance.
Solar Guppy wrote: »
I'm assuming your using a 500amp/50mv shunt which is 5% typical shunt tolerance and further effect your ah calculations.
RCinFLA wrote: »
Meant to comment on this earlier,
Eight month separation on manf. date on a new batch of batteries I was installing is greater then I would want to see.
trkarl wrote: »
RC you are right. The surrette site says that their dry stored batteries have a shelf life of five years and if stored longer will just take longer to activate with no ill effects. That is why I wrote no big deal especially on batteries that are supposed to have a life of around 15 years or more.
I should have did my homework and specified that all batteries have the same date and an extremely recent one as well but I didn't. So far they have performed extremely well after a year of service but I am not hard on them either.
My main problem with their quality control was the huge disparity of sg between the cells which should not have been there especially if they were all activated at the same time and same place in the same way. For a supposed superior battery manufacturer this seemed way out of whack.
I also noticed that now the specs on their site in pdf now rate them with a sg of 1.280 when before they were rated with an sg of 1.265 .
trkarl wrote: »
As far as the absorb v and time goes reading the different bulletins at the surrette site will give you different answers. I also talked to different rolls techs and each gave me a different answer.
I started out with the voltage set at 58.6 and absorb at 3 hrs but quickly found it was not enough. Over the course of a couple months I would test the sg of a couple cells each day sometimes at different times during the absorb cycle. If left at that setting the sg would steadily drop daily by a small amount.
Then I raised the voltage to 59.2 and went to 4 hours. Then I added more panels and now have it set at 58v and 6 hrs. It hardly ever gets to 6 hrs though. You just have to watch the water consumption and sg and you will get a feel for when they are at about 95+ % charged and whether or not you are overcharging them.
Also if I have several days of clouds on a sunny day right after that I will raise the voltage to make up for the deficit of the cloudy days. If several sunny days in a row I will prematurely float them instead of going through a complete absorb cycle but this is after taking an sg reading and comparing it to records.
I like taking a big hands on approach to my battery bank. I think why a lot of people ruin there batteries is because they think this is just a set it and forget it type of thing which I think is a big mistake. It's not like plugging in a dvd player. Each different site has different weather and temperature to deal with. All this has an effect on how the batteries charge and how deep they are discharged.
All this though is just relating my experience with my batteries and in no way should be taken as how you should maintain yours. You will have to decide that.