Navitron Renewable Energy and Sustainability Forum

Energy/Electricity Storage and Use/Grid Connection => Off-Grid, Batteries & Inverters => Topic started by: timbo on November 18, 2007, 01:00:55 PM



Title: Fork Lift batteries -worth buying?
Post by: timbo on November 18, 2007, 01:00:55 PM
I have found an ex-fork-lift vattery for sale and would appreciate any advice as to whether it is worth buying:

It is a Hoppecke 36 cells type oPZs 5 450 cell, originally 450Ah.

It was last used a year ago and has since sat, uncharged in a container.

The guy charged it for a few hours at 40A and it had stood 6 hours before I took these readings.

I noticed that the terminals felt quite warm...obviously some self discharge happening..is this serious?

Looking into the top of the cells they all have visible flakes of metal (Pb) lying flat on top of the plates. There seemed to be a risk that these will cause internal shorts?

1 2.097 V  1275sg
2 2.060 1260


Title: Re: Fork Lift batteries -worth buying?
Post by: timbo on November 18, 2007, 01:07:33 PM
oops...clicked "post before finishing....

3 2.073 1260
4 2.020 1200 (bad one)
5 2.089 1275
6 2.084 1260
7 2.058 1250
8 2.051 1240


these are typical of the 36 ( I measured them all).

I pulled a cell out of the box, unfortunately the sides ar opaque green so I can't tell how much is left of the plates but I think he would let me open of of the "dead" ones to see what has happened inside.

He says he knew someone who emptied the cells, steam cleaned all the flakes out and refilled them...I could do this. I wondered what happens to the huge stored energy (even in these partly chaged cells) if you drain the electrolyte out so they are open circuit inside. Is it a dangerous thing to do ?

Any advice welcome.

Tim.


Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on November 18, 2007, 08:37:25 PM
hi timbo,

if it were me and they were the right price i'd buy em, that is unless you were needing all of them. if the terminals were getting warm they probably just need cleaning. me i'd set the best 24 up in a 48v bank, give them a MEGA equalization charge, check the sg then see how they preform for a couple of days then re check the sg. dunno about the flakes right enough, the steam cleaner sounds a bit brutal, how about just replacing the electrolyte though it's probably quite expensive and dangerous :o could you tip it out and strain it ???

like i've said before i'm no expert ;D


Title: Re: Fork Lift batteries -worth buying?
Post by: timbo on November 19, 2007, 07:59:01 AM
HI,

Yes, I can tip it out and strain it so long as it won't cause any damage to dry them out...I still can't figure out what happens to all the stored energy if you just open circuit them!

I am going back this morning to see how the cells have held their charge...if they are pretty much as they were on saturday I'll haggle and see what I can get them for.

timbo


Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on November 19, 2007, 08:40:48 AM
good luck, dunno what happens to the sored energy either but i have emptied and refilled batteries before with no ill effect.

cheers, paul


Title: Re: Fork Lift batteries -worth buying?
Post by: timbo on November 19, 2007, 12:00:57 PM
Hi,

I measured the volages this morning and they had all drifted down by just 20mV so I haggled and got the whole set and frame for 150, which is not a huge premium over the scrap value if they turn out bad :-)

I'll put some pictures and a report hereb after I try reconditoning them as there doesn't seem to be much written about it online. (just lots of web sites, that look like scams, selling magic powders to put in each cell!!)

All being well , I should have 48V / 400 Ah after a bit of work, and will feel good about having recycled rather than buying new.

Tim.


Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on November 19, 2007, 09:33:27 PM
don't think you can go wrong at that price timbo ;D and you've got a few extra to play with 8)


Title: Re: Fork Lift batteries -worth buying?
Post by: timbo on November 23, 2007, 03:04:15 PM
So far, so good.....

I set up 24 cells and have run an equalisation charge with a 20A 24V charger on half the set, after 36 hours all the SG's came up to 1260.

The second set are coming up but ONE cell is stuck at 1175 SG, before I swap it, is it worth draining the acid, rinsing out with distilled water then refilling with new 1280 SG acid ? or is this a waste of time as the plates must be sulphated?

Tim.

(I stripped one cell down and there is a small amount of black sludge at the bottom but the 5 lead anode plates are still 8mm thick and should be good for years if I can clean the sulphate off.)


Title: Re: Fork Lift batteries -worth buying?
Post by: Ivan on November 23, 2007, 08:42:23 PM
I'm pretty sure you could revitalise the battery as you suggest - but first read up on safety issues. Working with lead is hazardous, especially if you are creating dust. Lead can be absorbed through skin, so it's worth being careful. Also, the waste material (whatever you scrape off the plates, and the sludge at the bottom) are hazardous, and shouldn't go in your dustbin or down a drain. You might be able to get it recycled at your local tip, if they collect car batteries (if you have an old battery, maybe you could put this stuff in through the vent holes and then recycle it)


Title: Re: Fork Lift batteries -worth buying?
Post by: timbo on November 23, 2007, 09:51:58 PM
Hi Ivan, I have considered the hazardous waste problem and was planning on disposing of the lead sludge as you suggested in some old tractor batteries delivered to the scrap yard.

I am going to try a complete re-build on some cells too, cleaning the plates with EDTA to completely remove the sulphate before re-assembly with fresh sulphuric acid, this should make them as good as new.

Tim.


Title: Re: Fork Lift batteries -worth buying?
Post by: pete-filldir on February 07, 2008, 11:50:40 AM
Tim how did you get on with your batteries?

Pete


Title: Re: Fork Lift batteries -worth buying?
Post by: Smooth Hound on February 10, 2008, 02:28:37 PM
i have also just bought some battery banks, i have one bank of 6x2 v batteries which is 250 amp hours, which i am thinking of putting in my caravanette, for power whilst i am away, if i charged them off a charger first before starting to use them, and then wired it up to the alternator , would that be ok , or would it be too much for the alternator. the other bank i have is a 400 ah 12v bank which i will use at home with my rutland 910, does that sound ok?, if anyone has any remarks or advice about this, or either of the ideas i have.


Title: Re: Fork Lift batteries -worth buying?
Post by: Smooth Hound on February 10, 2008, 03:02:07 PM
here is some pictures of them, i am thinking of replacing the wires screwed to the top of the 400 ah battery terminals, with jubilee clips and heavier wire.? everything about this for me is a question mark, as i am new to this, so anyone with anything to say about this would be welcome ;)


Title: Re: Fork Lift batteries -worth buying?
Post by: Smooth Hound on February 10, 2008, 03:08:51 PM
and these pics


Title: Re: Fork Lift batteries -worth buying?
Post by: Smooth Hound on February 10, 2008, 03:15:15 PM
and this


Title: Re: Fork Lift batteries -worth buying?
Post by: odbob on February 10, 2008, 03:31:51 PM
Tim,  This is an interesting thread, I have 25 (at least) years old cells forming a battery in the order of 25 KWhr, untill now, I hadn't even considered the possibility of cleaning them out, mine are clear perspex and I can see debris laying at the base of the cell, I have just one spare cell and may try this, if the plates are cleaned up does anyone know if this will virtually renew the cell, or is it more likely that the plates will be worn away anyway?

Can't upload my pics, my daughter tends to do this sort of thing for me and she's not here, can see them on my web though if anyone wants to look,  www.myhomeenergy.co.uk

Wish you luck with yours, there have been lots of useful comments


Title: Re: Fork Lift batteries -worth buying?
Post by: Smooth Hound on February 10, 2008, 04:00:18 PM
As far as i can understand so far, if the lead part isnt worn through or knackered then it will be able to be cleaned


Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on February 10, 2008, 09:28:28 PM
Firstly mate,

I've got a tea towel same as that ;D and secondly I wired some batteries up just like that a few years ago SH, stainless self tappers, copper wire, lead and battery acid  :o it was electrolasis paradise, lots of fur and corrosion very quickly so keep em tight and well vaselined.

Good luck, Paul


Title: Re: Fork Lift batteries -worth buying?
Post by: Bob on February 11, 2008, 07:16:51 AM
Smoothhound. 

Do replace those wires.  If I am doing something similar then I use old 3/4" copper pipe  and beat it flat, cut it into suitable lengths, drill holes in the ends and screw this to the top face of the lead with tech screws.  Works well as a high current conductor.

Timbo

There is a chemical that normally goes by the name of EDTA (something something tetra acetic acid) that has a fair reputation for being able to clean up tertiary sulfated plates.  I have used it on a couple of occasions with some beneficial effect.  It is a food additive and normally quite cheap.

I would echo Ivan's words on saftey.  A combination of weight, acid, lead and god-knows-what-else has the potential for being dangerous.


Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on February 11, 2008, 07:39:27 AM
Smoothhound. 

Do replace those wires.  If I am doing something similar then I use old 3/4" copper pipe  and beat it flat, cut it into suitable lengths, drill holes in the ends and screw this to the top face of the lead with tech screws.  Works well as a high current conductor.


I like that idea Bob  8)


Title: Re: Fork Lift batteries -worth buying?
Post by: Bob on February 11, 2008, 06:04:05 PM
Odbob

Quote
if anyone wants to look,  www.myhomeenergy.co.uk

Nice Cells!  Do they need cleaning?  I have something similar with a 5cm debris drop zone in the bottom.  It would probably take about 100 years to fill this with muck.  If they are working reasonably I would be loath to risk damaging them by unnecessary cleaning. 

Do yours have gray strips on the bottom under the plates?  If they do that is lead sulphate and would suggest that some of the acid is no longer available. Check the SG and top up with acid if necessary.


Title: Re: Fork Lift batteries -worth buying?
Post by: odbob on February 12, 2008, 01:19:45 PM
Thanks for looking Bob, and the advice very much appreciated :), yes there is a light grey coating right at the bottom of the debris drop zone as you call it, my drop zone is only 3.5 cm deep and there is general debris lying on the bottom, but there are just a few very large items of debris lodged in the upright touching what looks like a grey shield or separator of some sort, maybe to protect the lead plates? would these affect the performance?

Used to check the sg but tester eventually failed, must get a new one when I pass Halfords or somewhere

Thanks again


Title: Re: Fork Lift batteries -worth buying?
Post by: Smooth Hound on February 12, 2008, 04:47:32 PM
Thanks folks, the only other thing is , is will my transit alternator cope with the 250 ah bank, thats once ive given it its initial charge?


Title: Re: Fork Lift batteries -worth buying?
Post by: frank2 on February 12, 2008, 05:03:02 PM
smoothhound

i think your alternator will be ok, but i have found with mine, that if you let the voltage drop too low, the alternator has to work like mad and the belt starts to squeal

frank


Title: Re: Fork Lift batteries -worth buying?
Post by: Smooth Hound on February 12, 2008, 06:07:29 PM
great, so ill make sure they have a fair charge in yhem first, thanks for reply


Title: Re: Fork Lift batteries -worth buying?
Post by: billi on February 12, 2008, 06:32:06 PM
hi

 i just bought a 24 volt 1540 Ah  used 4 year old fork lift battery 

as far as i understand charging  you should charge them  with 10-20 %    , does this mean 150 a to 300 a  at 24 volt


my charger is 140 A    using a ac diesel unit.......

if i do build my own dc charger    what is the max Ampere you would recomend to charge this battery


thanks   billi


Title: Re: Fork Lift batteries -worth buying?
Post by: Shay on February 12, 2008, 07:02:05 PM
Billi,

Out of curiosity, how much did the battery cost you? It must be some weight!


Title: Re: Fork Lift batteries -worth buying?
Post by: billi on February 12, 2008, 07:44:38 PM
shay  they where not cheap and do not know if they are 100% ok  weight is close to 1.5 ton 

i did try a few ebay auctions (too days ago a similar batterry went on ebay for 360 serling)  i was just 5 pounds short   ...


but the one i bought now  is double the size and half the price for what you get new in this range


but i am excited   to find out if its in good shape


as far as i know you are based in ireland as well ?  so i tried a few fork lift companies in cork and suppliers for new ones   but got quotes upto  twice .....for the same battery quoted from the manufacturar in germany


i would have liked to get so called OPzS  2 volt cells  but went for this option for now


iam desperate for a battery , because my existing is not holding more then a 1kwh


paid today  transport arranged have to wait and find out

cheers billi


Title: Re: Fork Lift batteries -worth buying?
Post by: frank2 on February 12, 2008, 08:04:10 PM
billi

some photo,s of your proposed genny setup would be usefull, for advice


frank


Title: Re: Fork Lift batteries -worth buying?
Post by: Shay on February 12, 2008, 08:15:29 PM
Yes I'm in Westmeath Billi. Your shipping must cost he same as the battery?
I've been searching high and low for reasonably priced batteries. Have you or anyone else tried any of the battery recycling companies that have appeared. I wonder if they recieve any ups batteries from the likes of the financial services centre etc...just a thought...must call them to find out.


Title: Re: Fork Lift batteries -worth buying?
Post by: billi on February 12, 2008, 08:23:31 PM
frank

 i do have  a 6 kw inverter combined 140 A charger at 24 volts  that is feeded by a kipor , yanmar  ac generator and a pv array


 i just need two generators because on can fail  and i know this for fact  


from the start i should have got a real good one   to rellay on but monney wise i did it wrong,,,


so spended about 2000 pounds (or is it punts ?)allready on cr*p generators in one year  weather it was the headgascet or the generator ..... cheap buys



the kipor unit is ok and runs on an automated  systhem so pretty relaxed  


My max Ampere DC drom a AC generator will be 140 A  because of my ac/DC (highwaytohellunit)   but if i have the time and the balls id like to build a dc generator and think for that battery i can go 150 A or even 300 A  

the higher the A the easier is to find a watercooled engine  under 10 HP  its tricky under 20 HP more easy  



Title: Re: Fork Lift batteries -worth buying?
Post by: Gary T on February 12, 2008, 08:30:04 PM
       Have you looked at the deisel engines used in concrete mixers? I understand they go on for years with virtually no maintenance, have a single cylinder - I think around 500CC, and are I believe in the right power range. It should be possible to link one with a vehicle alternator.


Title: Re: Fork Lift batteries -worth buying?
Post by: Shay on February 12, 2008, 08:33:25 PM
Billi, 'Punts' were Irish 'Pounds' pre Euro currency


Title: Re: Fork Lift batteries -worth buying?
Post by: pete-filldir on February 12, 2008, 08:33:53 PM
Quote
i did try a few ebay auctions (too days ago a similar batterry went on ebay for 360 sterling)  i was just 5 pounds short

Thanks Billy, so it was you bidding against me!!!! :)


Title: Re: Fork Lift batteries -worth buying?
Post by: billi on February 12, 2008, 08:35:49 PM
shay shipping cost are about 400 euros per sqaremeter  in lorry from germany  upto 2,5 meters high


i wouldnot bodder with ups batteries only they are a bargain




Title: Re: Fork Lift batteries -worth buying?
Post by: frank2 on February 12, 2008, 08:43:03 PM
billi

i see, ideally you could use the kipor as a standby and a setup like frotter,s as the main genny (he gets 65a @ 48v so you could get 130a @ 24v) and you would get hot water too   ;D

frank


Title: Re: Fork Lift batteries -worth buying?
Post by: billi on February 12, 2008, 08:46:34 PM
Quote
Billi, 'Punts' were Irish 'Pounds' pre Euro currency

sound  

now i know and learn   for a german like me it was allways similar to pints  :P :P :P


have learned  now ;D ;D


Quote
Thanks Billy, so it was you bidding against me!!!!


iam happy not have to drive to england now with my trailor


i know about diesel mixers and have good  contacts for lister engines now

iam just waiting for a watercooled idea


cheers billi






Title: Re: Fork Lift batteries -worth buying?
Post by: frotter on February 12, 2008, 09:22:54 PM

 Mmmmmm... Kubota....!

http://cgi.ebay.co.uk/kubota-d722-engine-mini-digger-generator_W0QQitemZ200198153700QQihZ010QQcategoryZ64810QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


http://cgi.ebay.co.uk/KUBOTA-ENGINE-2-3-and-4-cylinder-bench-run-and-tested_W0QQitemZ290204620778QQihZ019QQcategoryZ95493QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 ;)


Title: Re: Fork Lift batteries -worth buying?
Post by: billi on February 12, 2008, 09:33:15 PM
cheers frotter

i like kubota engines   my little 3.5 ton digger is called Frida (name of mother in law   :P )


 i

like this mother...

http://www.ecycle.com/docs/KubotaAPU.pdf


Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on February 12, 2008, 09:58:36 PM
MMMMMMMMMMMMMM kubota  ;D

great engines for boats, diggers and welders but will it still be powering you house in 30 years ???

LISTER, thump, LISTER, thump, LISTER, thump LISTER  8)

(http://i224.photobucket.com/albums/dd170/camillitech/2020Small-1.jpg)


Title: Re: Fork Lift batteries -worth buying?
Post by: Bob on February 13, 2008, 06:29:07 AM
I have a Fiat three pot industrial in my main "Genny".  It has one or two problems but seems to go on and on.

"Jafa" (large orange Howard rotovator) is powered by a Hatz - very nice engine.

My Mayfield (scythe, barrow, aux genny, hay lift and anything else I can turn it into) is powered by a Changfa, a copy of the Yanmar L70 I think.

The water pump, just known as "Pump" has a Suntom, another copy of the Yanmar L70 I think.

And last but by no means least I have "Beton", my concrete mixer.  She has a Lister and was built in 1971.  I suspect that she will be turning when all the others have gone to the scrap yard in the sky.


Title: Re: Fork Lift batteries -worth buying?
Post by: SteveH on February 13, 2008, 11:38:16 AM
"Jafa" (large orange Howard rotovator) is powered by a Hatz - very nice engine.

 That brings back memories... Trying to start a "Howard Jem" on a cold frosty morning.. One guy on the the transmision starter handle & one on the direct engine starter... Great way to warm yourselves up... :laugh:

 Lovely tool to use... modern wheel drivens are far too light.. The "Jem" just needs light guidance & loose wrists.. They used to do a set of disk harrows with a seat on to tow behind... never got to use one, but that must have been rotavating heaven... ;D

 Sorry I went OT there... Must be me getting older... I'm developing a love of cardigans & already starting to tell people my age... :laugh:


Title: Re: Fork Lift batteries -worth buying?
Post by: frank2 on February 13, 2008, 02:23:56 PM
another off topic reminiscence  ::)
an old friend was cranking an old drott 1 cyl caterpillar plough (jockey wheel on a scroll decompressor, 2 man crank handle) and his  mate bottled it just when the jockey wheel dropped !
he woke up in hospital, with a broken jaw  :o


Title: Re: Fork Lift batteries -worth buying?
Post by: SteveH on February 13, 2008, 02:44:29 PM
  :o... I've seen the over prehensile thumbs after a kick-back... But just one word for that ...Ouch...  :-X

 Sorry OT again... :-[


Title: Re: Fork Lift batteries -worth buying?
Post by: billi on February 13, 2008, 09:05:11 PM
ok back to the point about batteries   

and forgett the point about my engine is better then yours,,,,,




 sow how to charge the fork lift battery at what amperage idealy   ?   a lister is an engine not.. not a god of alternator ...


so any idea beside the horse thats driving the charger ?


Title: Re: Fork Lift batteries -worth buying?
Post by: Bob on February 14, 2008, 07:18:37 AM
Hi Billi

In an ideal world, and depending on the starting condition of the cells you need to charge at between the C10 and C20 rate.  To explain.  If the battery is a 600Ah then the C10 is one tenth, ie 60A, and the C20 is one twentieth, ie 30A.

If the condition of the batteries is poor then start low and build it up to C10 rate.  Most commercial battery chargers, the sort that companies use to charge their forklifts, have quite complex sensing circuits for battery condition and timers to regulate the speed and depth of the charge.  Their are various periods in the charge cycle such as "bulk" and "float".

If you are just intending to run an engine and an alternator then you are limited to something between 30 and 60A.  It is possible to get vehicle alternators that do more or less but they are rare and expensive (unless anybody knows different?)

It is possible to use more than one alternator from the same engine to give 30A, 60A 90A etc.

Then you have the idea of "equalisation".  This is where you try to make the difference between the individual cells as small as possible.  Preferably less than 0.01v.  For a 24v battery you would normally  try to charge it until the voltage (under charge) was about 32v and hold it there for several hours.



Title: Re: Fork Lift batteries -worth buying?
Post by: billi on February 14, 2008, 08:48:10 AM
thanks bob


now i understand it better 




cheers billi


Title: Re: Fork Lift batteries -worth buying?
Post by: Smooth Hound on February 14, 2008, 12:22:54 PM
My transit alternator is 70 amp, if thats of any assistance, not too dear either if i remember rightly. you could even get one from a scrappy


Title: Re: Fork Lift batteries -worth buying?
Post by: billi on February 14, 2008, 06:28:05 PM
hi scrappy


i need 24 volt version  they are about 150 euros new on ebay 

cheers billi


Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on February 14, 2008, 09:00:08 PM
Hi Billi,

any standard, car, lorry, and even standard marine altenator will NOT charge up you batteries fully. It does not matter how many amps it says on the tin or how many belts are driving it, the regulator will stop it charging when it reaches a certain voltage (which is way too low for your battery bank) it does not matter weather it's a bosch, lucas, nippondenso, hitachi or wopping great CAV they are designed to charge up starter batteries and unless you have a more sophisticated (expensive) regulator you will never get the best out of your battery bank. As rob says you need either a 3 stage, bulk, absorbtion, float charger or even better 4 stage that will have an equalization facility, your inverter/charger will probably do this but no standard altenator will do this.

Good luck, Paul


Title: Re: Fork Lift batteries -worth buying?
Post by: billi on February 14, 2008, 09:49:41 PM
paul

my mx 60 solar charger will take car of the four stage charging including equalization (still have to find out more about this)   as well will my my combi inverter/charger

just need a spare generator to the one i have because donot like the idea  beeing without juice  like the others when national grid breaks down  ;D

thanks again for the input


bob by the way thanks again for your C10 and C20 coments i think i never understood that right so i think i overcharged my last battery a crab gel one by missunderstanding   i thought C20 ment double the Ampere

cheers billi



Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on February 14, 2008, 10:13:20 PM
paul

my mx 60 solar charger will take car of the four stage charging including equalization (still have to find out more about this)   as well will my my combi inverter/charger

just need a spare generator to the one i have because donot like the idea  beeing without juice  like the others when national grid breaks down  ;D





Sounds like a good plan to me Billi  ;)

Cheers, paul


Title: Re: Fork Lift batteries -worth buying?
Post by: billi on February 14, 2008, 10:22:40 PM
cheers paul


really i just want to play a bid..... and train myself for worst cases , just to learn  .....

found some pigs nearby  have to get two or three so lovely and intelligent   


Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on February 15, 2008, 06:10:58 AM
cheers paul


really i just want to play a bid..... and train myself for worst cases , just to learn  .....

found some pigs nearby  have to get two or three so lovely and intelligent   

I look forward to reading your posts about getting your genny to run on pig plop  ;D ;D ;D ;D


Title: Re: Fork Lift batteries -worth buying?
Post by: Darren8512 on February 19, 2008, 08:52:12 PM
Hi just fonud this on E-Bay

http://cgi.ebay.co.uk/DB-12V-Battery-Desulfator-extend-lifespan-Optimizer_W0QQitemZ350026247129QQihZ022QQcategoryZ15329QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

But it`s from Taiwan  and it`s max seams to be 200ah

Darren


Title: Re: Fork Lift batteries -worth buying?
Post by: PEMTEK on February 21, 2008, 09:20:37 PM
Alot of the new alternators are controlled by the engine ECU.

I believe the alternators have a load output so the ECU can measure what the current output is and also an input to control the output power. If a gadget was made this could be used to get a better charge if desired.

Several people on this forum are capable of making a controller to acheive this if more information was gathered about the control method.

Phil


Title: Re: Fork Lift batteries -worth buying?
Post by: Bob on February 22, 2008, 07:41:36 AM
DC motors make great battery chargers.  Phillips used to use them on some of their washing machines.


Title: Re: Fork Lift batteries -worth buying?
Post by: odbob on February 23, 2008, 02:21:22 PM
Bob, I finally got round to buying an sg meter and some interesting facts :- each of my cells read slightly higher than 2 volt and yet each cell has a specific gravity of between 1.225 and 1.150 ie showing discharged ?

You mentioned earlier about adding acid, is this a classic case of requiring that acid, ie without charging occuring and cell voltage of 2 plus volts, can I now add acid until the reading is 1.280 or thereabouts, what do you think?. interesting though, that the acid has disappeared in the first place, presumably some has disappeared into the grey strip at the bottom of the cell?

Anyone know what happens to the storage capacity when there is a week acid solution?


Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on February 23, 2008, 05:19:07 PM
Bob, I finally got round to buying an sg meter and some interesting facts :- each of my cells read slightly higher than 2 volt and yet each cell has a specific gravity of between 1.225 and 1.150 ie showing discharged ?

Hi OB,

I have three hydrometers (one of which cost 30 :o) and :- I'm quite obsessive about checking my battery banks and my neighbours. I also work on a ferry and have to check and record the SG of 5 battery banks weekly (for which we have 3 hydrometers) the one thing I can say with any certainty is that they all read different. In fact the 30 tells me my batteries are flat when they are equalizing ::) so I would be more concerned by variation than actual figures and from your readings I would be concerned :-\ but like I say I am a bit obsessive about my batteries. I really should get out more!

Good luck, Paul


Title: Re: Fork Lift batteries -worth buying?
Post by: Bob on February 24, 2008, 07:02:04 AM
I agree with Paul about hydrometers.  Every single one gives a different reading.

If you have the gray stripe then you have lead sulphate that has dropped off the plates.  I have the same.  If my old chemistry lessons remain in the addled brain then it goes something like this:

When the battery discharges some of the sulphate (SO4-) ions come out of solution and stick to the plates as PbSO3

The other O atom combines with two H+ ions and forms water.

Charging reverses most of this but not all of it.  The chemistry of lead and oxygen is complex.  There are many lead oxides and some of them cannot be changed back.  You get a stripe.

I have jst found this useful little diagram


Title: Re: Fork Lift batteries -worth buying?
Post by: odbob on February 24, 2008, 09:20:13 AM
Thanks for your replies, but am still somewhat confused :-\, as a for instance what's the point of sg meters if they are so inaccurate ?, why do we need to check sg ?, what happens if the acid portion is lower than it should be?.

I think that I will purchase some sulphuric acid and add small amounts to the cells in an attempt to bring the sg count closer to that which it should be, ie 1.280

I have read the label on these cells and contrary to my earlier posts, they are 24 years old this month :)


Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on February 24, 2008, 02:09:21 PM


I have read the label on these cells and contrary to my earlier posts, they are 24 years old this month :)

Hi OB if they are 24 years old I wouldnae waste your money on sulphuric acid and have MI5 looking for you on the assumption that your using it to make expolsives ;D, As far as the hydrometer goes it's beyond me why they're all cr*p and I've often wondered, as far as their purpose in life goes on allot of batteries nowadays the terminals are in the casing so you can't measure individual voltages also I find that you can take an SG reading whilst the battery is still under charge whereas voltage readings need to be off charge and settled for a while.With many renewable energy systems they can be charging for allot of the time. my wind turbine has been dumping 2kw since wednesday morning :o

Cheers, Paul


Title: Re: Fork Lift batteries -worth buying?
Post by: Bob on February 25, 2008, 07:12:09 AM
Morning Paul

What explosive do you make with Sulphuric?  Nitric - Oh Yes!! :angel:

Bob,

24 years is a long time.  How big are they and how easy are they to drain?  Any chance of a pic?

Possible method.

Drain cells
Fill with very how saturated solution of EDTA
Allow to cool and stand for a week
Rince with distilled water
Rince again and again.
Refill with new acid
Curse me for suggesting this plan!


Title: Re: Fork Lift batteries -worth buying?
Post by: odbob on February 25, 2008, 10:22:27 AM
Bob, you saw these before on my web site    www.myhomeenergy.co.uk   they're similar to yours, it's yourself that suggested I look for a grey strip at the bottom, which I have got :(

They seem to be doing a good job and so I don't necessarily want to do too much to them, but having obtained an sg meter, am now worried that the sg is far too low at 1.220 average at fully charged state, having read all the various comments I'm now inclined to top up with acid water mix which I can obtain from my local battery supplier, this solution is already mixed to sg 1.280

Thanks for your advice but it sounds far to complicated and messy :-[

No one has wished them happy birth month :(

I am hoping they will last me until the rules are relaxed with regard to grid connection and until inverters become more affordable


Title: Re: Fork Lift batteries -worth buying?
Post by: Bob on February 25, 2008, 07:37:14 PM
When I got my big ones they had a low SG.  I topped them up with concentrated sulphuric (hat, mask, gloves, plastic coat, wellies, buckets of water handy).  That worked really well.  Takes a while as you have to do it in stages.


Title: Re: Fork Lift batteries -worth buying?
Post by: Paulh_Boats on February 25, 2008, 08:26:45 PM
List,

You can calibrate hydrometers with distilled water; they should read 1.000 at room temperature.
So if they read 1.05 in distilled water then subtract 0.05 from all the acid readings you take.

-Paul


Title: Re: Fork Lift batteries -worth buying?
Post by: camillitech on February 25, 2008, 09:58:44 PM
Morning Paul

What explosive do you make with Sulphuric?  Nitric - Oh Yes!! :angel:

Bob,




 ::) A little knowledge is a dangerous thing, I'd make a lousy terrorist Bob  ;D


Title: Re: Fork Lift batteries -worth buying?
Post by: Shay on February 26, 2008, 12:27:16 AM
You do realise Bob that you have probably have been tagged by CIA/Homeland Security software and a Jack Bower type operative is in your back garden! ;D


Title: Re: Fork Lift batteries -worth buying?
Post by: Bob on February 26, 2008, 07:20:43 AM
Hi Shay,

Then he had better tell Chloe that "there isn't much time!"  I hope he brought his wellies, it's been raining for 24 hours and the river's high.

I don't like 24 but my beloved and daughter are addicts.  They have them all on DVD  :(


Title: Re: Fork Lift batteries -worth buying?
Post by: odbob on February 27, 2008, 09:27:28 AM
I have now purchased 1260 acid mix, 25 litres ( can't buy neat acid ) and will now remove some of the old mix and replace it with this, the sg will not be sufficient, but better than before, I will use the remainder over a period of time, topping up instead of using my distilled water.

Oh and to an earlier posting re sg meters being inacurate, I have now tested mine ( a 1.99 jobby from the local car spares man ) in this new solution and it reads more or less 1260, good enough for me


Title: Re: Fork Lift batteries -worth buying?
Post by: Bob on February 28, 2008, 07:20:05 AM
Where did you try to get the acid?

I find that printing a purchase invoice from (Bob's Battery Service plc) an heading off down to the nearest chemical supplier normally works.


Title: Re: Fork Lift batteries -worth buying?
Post by: odbob on February 28, 2008, 12:04:22 PM
Bob, good idea, but too late for my purchase, I just got it from my local battery supplier, it'll do the job to a degree, and certainly the end result will be better than before so I'm OK with this, thanks for your help

Bob, ( Odbob )