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WineGuy

Newbie

Joined: 16/04/2008
Location: United States
Posts: 10

Posted: 05:45am 25 Feb 2009

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This a re-cap of a five month attempt at battery conditioning.
Batteries in the group:
    One 3 year old battery, purchased new
    Three batteries with little or no electrolyte, age unknown,
Methods attempted:
    Smart charger with float mode.
    Trickle charge
    Desulfator
    EDTA.
Lesson 1: DO NOT bother with different sized batteries with differing histories. It does not pay. The batteries must be used in a group of similar (identical) sizes,
capacities, and histories in order to act the same under charge/discharge cycles.

Lesson 2: Desulfation works, up to a point. All of the batteries was brought back to (almost) good condition with simple trickle charge, but improved even farther with Desulfation (pinging). One battery came back to almost new condition,

Lesson 3: A battery analyzer is a REALLY neat tool. Measuring specific gravity and voltage helps, but knowing internal resistance, and KW helps pull them
together to determine the state of the battery.

Lesson 4: The jury is still out on EDTA. It removed a lot of junk from the batteries, but the end result showed no difference so far. I'm still working on the technique and will add more later.

One of the best testing methods I used was an inverter, 100 watt light bulb,and an analog clock. I charged the battery, put it on the inverter, and let it run
until the inverter stopped (around 11 volts), which stopped the clock. Read the clock to see how many amp hours the battery produced.

You should probably add a diode between the battery and inverter to keep the final voltage above 11 volts.
I repeated the above sequence twice with the smart charger, twice with the trickle charger, and three times with the desulfator and trickle charger. The desulfator and trickle charger produced the best results. The smart charger produced up to four hours of run time, the trickle charger produces up to 8. The desulfator and trickle charger (third try) lasted 18 hours. One of the batteries actually ran for 28 hours. This was one of the "dry" batteries.
I'm still playing with the EDTA, so I have no really good data to post yet.

Sure wish I was smart instead of so darn cute!

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 06:22am 25 Feb 2009

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Hi wineguy,

I have similar experience with these smart chargers. I have switchmode, 24V, boost > float type.

These chargers don't really charge the battery fully, but are useful to recharge a battery that has been taken down a long way. These are current limited and bring the volts up enough to reduce the liklihood of sulphation. The windmills do a much better job of replacing the kW. I have the full battery maintenance charging reigime on my 24V battery and this seems to be working well with the windmill.

The battery is still the weak link, but is the most convenient for most RE users at the moment. I would prefer elevated water storage, but I have no mountains close to where I live.

Gordon.

become more energy aware

matt down south
Regular Member

Joined: 20/10/2007
Location: Australia
Posts: 50

Posted: 03:13pm 27 Mar 2009

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hi all
i often get car batteries from a servo close by and have had good results with the desulvator i got from jaycar using the same methods wineguy has described,serveral of my mates have fitted them to their hardly used 4wd's and reported how the starter motor spins their big diesels over much quicker

matt

matt

Bernie the Bolt

Regular Member

Joined: 26/10/2006
Location: United Kingdom
Posts: 45

Posted: 07:44pm 11 Apr 2009

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Bonjour Wineguy (I live in france)
I would be interested in your findings re initial voltages of your scrap batteries B4 desulphation. I have had limited results with some 80 - 125 amphour leisure batteries (ex RV) Some were less than 10.5 volts and did not respond. One was low on electrolyte but measured over 12v and has responded to being left for three months on a pulser with a 1amp trickle charger plugged into a rotary timer set for about 6 hours a day.
Some one on this forum suggested batteries with less than 10.5 volts are not worth bothering with - do you agree ?

Bernie the Bolt

I'd rather be sailing!

Bernie the Bolt

Regular Member

Joined: 26/10/2006
Location: United Kingdom
Posts: 45

Posted: 07:51pm 11 Apr 2009

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Also I believe a low voltage indicates a cell has an internal short - possibly caused by dendrites, and I understand shorting the battery across it's terminals can help remove these. I have read a more complex version of a pulser is available that does this automatically (in milliseconds).
What are your's or anyone elses thought on this ?

Bernie the Bolt

I'd rather be sailing!

WineGuy

Newbie

Joined: 16/04/2008
Location: United States
Posts: 10

Posted: 02:02am 28 May 2009

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Hi Bernie,
My experiment used "junk" batteries to start with. Two were dry, so no voltage. I just added distilled water and started the procedure. The both look to have a weak cell, but I'm not giving up yet.

One of them was sitting around 8 volts (from memory). This battery ended up being the best one I have.

If you are looking for a "learning experience", the starting voltage does not matter. This way you can try everything, and if you destroy the battery it does not matter,

If you want a usable battery when done, it is probably wiser to start with higher voltage.

Sure wish I was smart instead of so darn cute!

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