Fulmen Forklift Batteries

Brianellul

Hi

I have come across some brand new Forklift batteries. The owner told me that these are FULMEN 2v 680AH (20cm width x 12cm depth x 46cm tall). These have never been used and I managed to convince him to bring over one cell to my house to inspect it. The terminals do tell me that they have never been connected, and actually this is my worry! I have no clue how long they have been standing uncharged in his garage.
The water level was almost OK, not more than 4 cm of plates exposed. I checked the voltage and found it 1.65v. The SG was 0, i.e. the hydrometer did not even move, as if I was measuring water.
I connected a small charger (max 10Amps) to charge this beast. Unfortunately, I could not connect my 12/24v charger across just 1 cell so I had to let this small charger do the job. Well after 4 days, the SG came up to 1.28. Did not measure the voltage yet…. Since I’ll leave the battery resting for now however it should be fully charged.
This guy is asking me 110 Euros (US$ 150) for each cell battery. I need guidance here. Is the price OK for brand new however left uncharged batteries? It’s OK if the capacity is less than 680AH however I need to know beforehand so I won't be buying scrap and maybe I can negotiate a better price.
What tests can I perform on this battery to measure its actual capacity?

Regards
Brian

vtmaps

Re: Fulmen Forklift Batteries

Brianellul wrote: »

The water level was almost OK, not more than 4 cm of plates exposed.

Do not ever buy a wet battery with exposed plates. --vtMaps

H2SO4_guy

Re: Fulmen Forklift Batteries

These are worth about $.28 per pound as scrap in my area. If I were buying them I would offer about $.35 - $.40 cents per pound, because it is a crap shoot at best. They will have reduced capacity and may not work at all, so only gamble what you can afford to lose. Good luck and let us know.

mike95490

Re: Fulmen Forklift Batteries

not more than 4 cm of plates exposed.

they are toast. sorry, it's not a deal at all.

Even for free, you will be sore from installing them, and then scrapping them the next week.

stephendv

Re: Fulmen Forklift Batteries

Brianellul wrote: »

This guy is asking me 110 Euros (US$ 150) for each cell battery. I need guidance here. Is the price OK for brand new however left uncharged batteries?

Too expensive to warrant the risk. I paid 133 Euro per cell for similar sized batt shipped brand new from factory. Shipping costs to Malta must be quite steep, but perhaps you could try suppliers based in nearby countries, e.g. www.sunlight.gr (where I got mine); or http://www.celectric.eu/ ; or www.moll-batterien.de; or www.fiamm.com; or http://www.hoppecke.com/

Brianellul

Re: Fulmen Forklift Batteries

Hey guys. Thanks for all your responses!

Yes as I suspected, not to much confidence in these batteries, however it's the exposed 4cm of plates (out of 46cm - battery length) which actually started me to enquiry about how can i measure the actual capactity of these batteries since it will be lower than the manufacturer. Is there an article/set of steps I can follow to measure the battery actual capacity, for example loading it with a fixed load for x hr?

Also, just to confirm, I have about 1KW (peak) of panels which I can use to charge these batteries. I have seen a max of ~30Amps (24v system) going into my current batteries. This is way to low to charge/maintain these supposed 680AH batteries? A better fit for me will be ~300AH. Correct?

Regards
Brian

BB.

Re: Fulmen Forklift Batteries

The general rule is 5% to 13% as being a good range for solar charging.

For Forklift batteries, some mfg. recommend 10% minimum rate of charge (and older forklift batteries will have higher self discharge current).

So 10% of a 680 AH fork lift battery bank would need ~68 amp minimum charging current.

680 AH * 29 volts charging * 1/0.77 panel+controller derating * 0.10 rate of charge = 2,561 Watt array minimum

You can monitor the float current... An "old" about to be replaced forklift bank will stabilize at ~1-2% rate of charge (self discharge). You might also see the bank starting to get warm/hot just from self discharge (not a good thing).

-Bill

mike95490

Re: Fulmen Forklift Batteries

when plates are exposed, chemical changes begin to happen, and then the whole bucket of battery, plates and electrolyte, gets messed up. And with being un-tended for so long, to evaporate water and expose plates, they likely sat discharged for some time too. I'd pass on them, or at least insist on a honest Load Test of them.

Brianellul

Re: Fulmen Forklift Batteries

Hello guys

OK, so finally I charged the battery. Took me a bit long because I don't have a 2v battery charger, and instead I used a bench variable power supply, maxed to 10amps for almost 4 days!
So the resting voltage is now 2.11 and 1.28SG.

I connected a small load across the battery to perform the discharge test. Again, I didn't have 2v lamps and instead I used multiple 12v lamps. Maximum load was about 3.3amps.

Discharge Current Voltage SG
3.3 amps 1.98v 1.28 (Started discharge test)

24 hours later
3.3 amps 1.90v (Voltage taken while under load)

27 hours later
3.3 amps 1.87v 1.24 (Voltage taken while under load)

23 hours later
3.3 amps 1.84v 1.21 (Voltage taken while under load)

11 hours later
3.3 amps 2.01v 1.19 (Resting voltage after discharge test)

Summary:
85 Hours Discharge Test
Voltage: 2.11 --> 2.01
SG: 1.28 --> 1.19

Does anyone have some documentation to better interpret the data which I logged? I just want to confirm what is the batteryn actual capacity based on my tests. Any help is greatly appreciated.

Regards
Brian

Brianellul

Re: Fulmen Forklift Batteries

OK so I think that I'm making progress....

The battery original AH was 680AH at the 20Hr rate which means that 680/20=34amps. The battery should sustain 34amps for 20 hours before it's flat.

Therefore, in my case, I discharge the battery to 50% (according to the SG). So I can work on a 340AH battery. I discharge for 85hours. Therefore 340/85=4. In theory, a discharge current of 4 amps can be sustained for 85 hours. In my case, I used a slightly less current (3.3amps). Therefore it seems that the battery capacity is 3.3x85=280Ahx2=561Ah, almost 100AH less than what is originally sold for. Am I correct? Can someone please verify my reasoing and workings?

Can it be that the battery is still not at it's full potential simply because it has never been cycled before or maybe it's already sulphated?

If I have to purchase these batteries, I need to know exactly in what state they are before I fork out any money. Granted that some people told me to forget them however I want to make sure that the batteries are toast before dropping out the deal.

waynefromnscanada

Re: Fulmen Forklift Batteries

Sorry man. May sound like a great deal for the money, but they were left sitting discharged for who knows how long and the plates were exposed. It's your money and I wish you could get a great deal, but personally I wouldn't touch them with one of those proverbial 10 foot poles. So sad that what could be awesome batteries were murdered.

65DegN

Re: Fulmen Forklift Batteries

When batteries are discharged over longer periods of time at lower current levels the AH capacity increases substantially. It is non-linear.