Battery Equalizer Fluid

Cariboocoot
Cariboocoot Banned Posts: 17,615 ✭✭✭
I'm trying this on a couple of older batteries I've got which are sulphated:

http://alexmilne.com/resources/pdf/battery_equaliser.pdf

The website gives nothing along the lines of technical details, except implying it is environmentally safe. I therefor presume it's not the same as the old "VX-6" additive, which was cadmium based I think. There's another from the Solder-It company called "Charge-It" which I think is similar to VX-6, but I can't find that locally.

Anyway, I thought I'd try this out and let everyone know the results. It says it takes "five cycles" to achieve maximum results. Don't expect much; I don't! :p

Batteries are Group 27D Marine 'boat' batteries, approximately 2 years old. Cell SG to start with:

Battery 'A'
1) 1150
2) 1175
3) 1225

Battery 'B'
1) 1125
2) 1100
3) 1175

Nothing like giving it a real test, eh? :p

Comments

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Battery Equalizer Fluid

    seeing as how the temps are beginning to drop that you may want to record the battery temperature when the sg readings are made.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Battery Equalizer Fluid

    Very good point, Niel. Wouldn't be fair test otherwise!

    Last night the temp inside the cabin dropped 20 degrees F. What that does to my batteries' SOC is worse than the over-night usage.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Battery Equalizer Fluid

    First off, BRILLIANT of me to have left off posting half the cells' SG readings to begin with! :blush:
    That's what you gt for writing things down willy-nillu on scraps of paper. Shall we try it again?

    Starting SG:

    Battery 'A'
    1) 1150
    2) 1175
    3) 1225
    4) 1175
    5) 1175
    6) 1150

    Battery 'B'
    1) 1125
    2) 1100
    3) 1175
    4) 1125
    5) 1150
    6) 1175

    Now after five days of charging, absorbing, and equalizing with the battery fluid (20 ml per cell):

    Battery 'A'
    1) 1225
    2) 1225
    3) 1225
    4) 1250
    5) 1250
    6) 1250

    Battery 'B'
    1) 1250
    2) 1250
    3) 1250
    4) 1225
    5) 1225
    6) 1175 (something wrong with the cell, perhaps)

    Note: these readings are "within the range"; my eyesight isn't good enough to read a hydrometer any better than 0.025

    Clearly there was an improvement, but the question still remains: is it due to the Battery Fluid or is it simply due to repeat charging and equalizing?

    I think the next part of the test will be to see if the SG will remain high.
  • Slappy
    Slappy Solar Expert Posts: 251 ✭✭✭✭✭✭
    Re: Battery Equalizer Fluid

    Clearly there was an improvement, but the question still remains: is it due to the Battery Fluid or is it simply due to repeat charging and equalizing?
    Time will tell, but keep us updated here and their, if possible! I have a couple of batts that I would like to restore/or get some extra life out of;)
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Battery Equalizer Fluid

    Okay, so I did the experiment wrong. I was too caught up in 'save the batteries' and didn't really think about objective testing.

    Obviously I should have added the Battery Equalizer Fluid to only one of the batteries, and then charge both of them in the same manner. That way you could tell if there was more of an improvement from the BEF or whether both batteries gained the same - indicating it was the charging that did the trick.

    Always nice to realize these things 'after the fact'. Oh well. At least people can learn from my mistakes.:p
  • tallgirl
    tallgirl Solar Expert Posts: 413 ✭✭
    Re: Battery Equalizer Fluid

    The primary ingredient is Cadmium Sulfate.
  • mshen11
    mshen11 Solar Expert Posts: 185 ✭✭✭✭✭
    Re: Battery Equalizer Fluid

    ive got a question...

    in a controlled setting where you have a bunch of battery w/ no addition of this chemical, and you equalize, charge, etc... them together. when they in theory lose the same amount water?

    ive got a new set of battery and i dont know if it is my imagination or my bad sense of judgement on how topped off the cells are but i seem to have to put different amounts of water in each cell. im wondering if that is normal?

    also i noticed a pattern - if the sg of a cell is high that means it needs more water than one that is low. is that the proper usage of the sg number? and to get a true sg of the battery i would have to top everything off, equalize them AGAIN and then read the sg?

    also is there such a thing as an electronic/digital hydrometer that is of good quality? everyone has these float tubes and its hard to read - and also im doubting myself on how to read them. doesnt help if the acid makes me worry of spilling (no pressure there).
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Battery Equalizer Fluid
    tallgirl wrote: »
    The primary ingredient is Cadmium Sulfate.

    For VX-6 and Charge-It additives it is. I can't find any info about this product specifically, but it probably is as well.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Battery Equalizer Fluid
    mshen11 wrote: »
    ive got a question...

    in a controlled setting where you have a bunch of battery w/ no addition of this chemical, and you equalize, charge, etc... them together. when they in theory lose the same amount water?

    In theory, yes. But no two cells are ever exactly alike, much less two batteries.
    ive got a new set of battery and i dont know if it is my imagination or my bad sense of judgement on how topped off the cells are but i seem to have to put different amounts of water in each cell. im wondering if that is normal?

    It depends on the amount of difference. Are we talking about an ounce or a cup of water?
    also i noticed a pattern - if the sg of a cell is high that means it needs more water than one that is low. is that the proper usage of the sg number? and to get a true sg of the battery i would have to top everything off, equalize them AGAIN and then read the sg?

    SG = Specific Gravity. It's a method of measuring the density of the fluid, and is expressed in relation to pure water which has an SG of 1.000. As you charge a battery, some of the hydrogen and oxygen is turned into gas - essentially reducing the volume of H2O in the sulphuric acid leaving it more dense, thus a higher SG. There is quite a bit of debate about the perfect way to read SG, but given the innumerable variables the best way to do it is consistently; in other words, you compare this month's reading to last month's and look for change, just as you compare one cell to another to look for differences. Small differences are normal. The 'true' SG is whatever you read at the time of reading it; adding water will lower it. Hopefully you won't be adding so much water that it will make a significant difference. A just-charged battery's SG will be high, say 1.275, and will reduce slightly when the level is topped up, say 1.265. Both indicate a charged battery.
    also is there such a thing as an electronic/digital hydrometer that is of good quality? everyone has these float tubes and its hard to read - and also im doubting myself on how to read them. doesnt help if the acid makes me worry of spilling (no pressure there).

    I know what you mean about hard-to-read. :cry: My eyes are older than yours! :cry: There is such a thing as an electronic hydrometer: http://www.densityanalytics.com/
    Personally, I wouldn't bother. Since all such standards are arbitrary anyway, if you take your base readings when the battery is new and take subsequent readings in a consistent manner you'll have a fairly accurate idea of how it's performing. It's practically impossible to get down to that 0.001 part.
  • mshen11
    mshen11 Solar Expert Posts: 185 ✭✭✭✭✭
    Re: Battery Equalizer Fluid

    what i meant is... is there a good digital hydrometer that doesnt cost an arm and a leg. the site didnt list the price - thats never a good sign.

    so if you read it "consistently wrong" it is good enough? since everything is relative.

    also what is considered abnormal amount of water to add for a cell? im sure 1 cup is. btw on a topped off cell, how much fluid is there there?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Battery Equalizer Fluid

    Loss of water is the result of overcharging/equalization... For a flooded cell, some water loss is normal--and even good (mixing electrolyte, equalizing between cells). No water use may mean that the cells are not getting enough charge.

    If your cell plates are almost exposed every month (after a fill the month before)--my guess is that you are overcharging the battery bank.

    Variable water usage in a bank--you might have electrical problems (wiring, connections) and the batteries are not properly sharing current (and some batteries in the bank are not getting a full charge). The string with less water usage may have an open cell. The string with heavy water usage may have a shorted cell, etc.

    The act of equalization is not a benign process... Oxygen is formed on the positive plate and can accelerate positive plate/grid failure (oxygen based corrosion) if too much equalization is performed over time.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Battery Equalizer Fluid

    Bill brings up a very good point about equalization. It is rough on batteries. Some sources tell you to equalize every month, some say four times a year. I say check the SG every month, and EQ only if there's a significant difference across the cells - at least 0.025. I'm sure other people have their own opinions, based on their personal experiences.

    And yes the water loss from charging should be minimal. Most of the time I get through 30 days without adding so much as a teaspoon full. There is a range of acceptable level; from 1/4" above the plates up to the bottom of the fill well. Don't get obsessed with the idea that everything has to be exact down to four decimal places. You can go mad that way! :p

    I'm going to start that 'battery charging' thread any day now ...
  • Ralph Day
    Ralph Day Solar Expert Posts: 1,019 ✭✭✭✭
    Re: Battery Equalizer Fluid

    Say Marc,
    Any opinion yet on the Battery Equalizer fluid? Would you use it on your best set of batteries?

    Ral;ph
  • tallgirl
    tallgirl Solar Expert Posts: 413 ✭✭
    Re: Battery Equalizer Fluid
    For VX-6 and Charge-It additives it is. I can't find any info about this product specifically, but it probably is as well.

    An MSDS (Material Safety Data Sheet) can be your friend. When in doubt, find the MSDS for the product.
  • tallgirl
    tallgirl Solar Expert Posts: 413 ✭✭
    Re: Battery Equalizer Fluid
    BB. wrote: »
    Loss of water is the result of overcharging/equalization... For a flooded cell, some water loss is normal--and even good (mixing electrolyte, equalizing between cells). No water use may mean that the cells are not getting enough charge.-Bill

    No water use may also mean the proper balance between charging and discharging. I ran my house fairly "off-grid" while waiting for my utility (TXU Energy) to stop ripping me off. During that time the state of charge was controlled more by computer than by my MX-60. The result was remarkably little water loss, and that was at a time when I sold less than 50KWh total of what should have been more than 1MWh.

    The key is knowing when to end the "Absorb" cycle. Forget about equalization -- it's hours and hours in "Absorb" that are what I think uses so much water. "Absorb" should be ended when the return current reaches, and maintains, a low value. That's it -- switch to "Float". Once a week or so, do the longer "Absorb" cycle, but the routine daily many-hours-long absorb cycles I read about are not good for batteries.
  • Ralph Day
    Ralph Day Solar Expert Posts: 1,019 ✭✭✭✭
    Re: Battery Equalizer Fluid

    But Julie,

    If I don't have hours of absorb my sg readings don't get up to full charge status. SOmetimes i've used the MX60's cutoff feature (can't remember what it's called) at 2 amps, and if there's wind the cc will revert to float...less amps going in from the mx due to the wind input, and poof, but not at full charge.

    I will say that during some extended periods of sunny days and I'll check the number of amps required for absorbing and trip the mx to float, but only when the sg reflects full charge status. Doesn't happen in fall and winter.

    Ralph
  • tallgirl
    tallgirl Solar Expert Posts: 413 ✭✭
    Re: Battery Equalizer Fluid

    Ralph,

    Read to the end of the post -- I'm not suggesting you never leave your batteries in "Absorb" for hours on end.
  • Ralph Day
    Ralph Day Solar Expert Posts: 1,019 ✭✭✭✭
    Re: Battery Equalizer Fluid

    Julie,
    What do you mean by return current? Do you mean the current going to the batteries being a low value? A certain number per ah for 20hr rate?

    Thanks
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Battery Equalizer Fluid

    I'm about to close this place up for winter, since Mrs. is being released from hospital tomorrow. We'll be in an hotel for awhile before she's able to travel.

    So here are the results from my un-scientific test, after however long it's been with erratic charging/discharging (battery torture) on these 'secondary' batteries that just run a MSW inverter in the gen shed (I know that sounds ridiculous). For the final results I fully recharged them and ran a 1 hour EQ.

    Battery 'A'
    1) 1250
    2) 1250 (low on water)
    3) 1225
    4) 1275
    5) 1275
    6) 1275

    Battery 'B'
    1) 1275
    2) 1250 (low on water)
    3) 1275
    4) 1250
    5) 1250
    6) 1175 (definitely something wrong with this cell)

    As you can see, there was some improvement from the starting readings. But by no means can this be considered a rollicking success. There is still an inconsistency in SG between cells in each battery, and two of the cells used significantly more water than the rest. The very low cell remained unchanged. If this Battery Equalizer Fluid was really good, I'd expect to see more consistent results. It's my opinion that it was the recharging and EQ cycles that are responsible for the improvement, not the BEF.

    But I've already admitted where the flaw in the testing lies. So as usual, your actual results may vary.