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Old 08-10-2010, 09:58 AM
F16bmathis F16bmathis is offline
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Angry Killing Lead Acid batteries

I've now overcharged my Trojan T-105's at least four times. I usually leave the charger to do its thing overnight, and twice I've come out around noon to find its still trying to charge the batteries, which are smoking, at 180 degrees F, and have dumped battery acid all over my driveway. I've re-filled them with water, but I suspect too much acid is gone. Some cells show no Specific Gravity at all, others show an overcharge.

What happened? Did I have a dead cell that made the charger think I still needed charging? Were the batteries too hot?

The truck is now parked. I'm done.
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  #2  
Old 08-10-2010, 10:23 AM
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Default Re: Killing Lead Acid batteries

Sounds like yu have a shorted cell or two so the voltage never gets high enough trip the charger circuitry to turn off. This is why it is a good idea to also have a timer to prevent such things from happening.
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Old 08-10-2010, 11:19 AM
F16bmathis F16bmathis is offline
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Default Re: Killing Lead Acid batteries

I should've used a timer after the first overcharge. I thought I'd have remembered to unplug it before I went to bed. Ha!

I guess I have time to install a timer and a few other goodies before I can go with lithium. You think I'll be smart enough to get a BMS then?
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Old 08-11-2010, 10:04 AM
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Default Re: Killing Lead Acid batteries

What brand of charger were/are you using??

Yes, you might have a shorted cell before. With the "missing acid", sounds like more than one cell/battery is being vastly overcharged. Check your charging voltage, expecially the finishing/EQ voltage. My EQ amperage is about 4Amps.

Let batteries set for 24hr after charg, then use a good digital voltmeter and check the (resting) voltage of each battery. When batteries bubbled over, you lost acid. You would probably need to check the specific gravity of each cell on each battery (assuming floodies). It's difficult to ADD acid accurately to
reconfigure to the factory specific gravity.

You will probably just have to "write it off" as a learning experience.
A real-time BatteryMonitor on each battery would tell you which battery(s) are showing signs of more/excessive voltage drop under load as you drive.
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Old 08-11-2010, 12:01 PM
F16bmathis F16bmathis is offline
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Default Re: Killing Lead Acid batteries

The charger is a Manzanita. I had used the Specific Gravity tool to check the cells charge levels and found 7 bad batteries. Battery voltages were anywhere from 6.2 to 6.8 (6V batteries). I had a Pak-Traker to monitor the batteries, but it ALWAYS went crazy when driving, so its sitting in the garage now. Yes, I did everything except shieiding every wire.

I'm going to try add acid to low batteries in the hopes of bringing them back to life with the help of the battery supplier (SBS). Other than that, its all a write off till I can afford lithiums. Should've gone that way from the begining, but tried to save money!

Maybe I'll throw the Pak-Traker back in and sheild every wire... if I get the batteries back from the dead.
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Old 08-11-2010, 05:23 PM
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Default Re: Killing Lead Acid batteries

Quote:
Originally Posted by F16bmathis View Post
Maybe I'll throw the Pak-Traker back in and sheild every wire... if I get the batteries back from the dead.
Don't waste your breath on shielding Paktrakr, its useless. Noise doesn't come from air, it comes from wires themselves. I did everything there is to fix my PakTrakr. The only fix is to remove it and use something else.

I thought Manzanita has a timer and adjustable voltage? Its a pity when most expensive charger ruins the pack. You could have paid for half the lithium pack with what you spent on Manzanita and Lead.
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Old 08-11-2010, 08:00 PM
F16bmathis F16bmathis is offline
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Default Re: Killing Lead Acid batteries

The Manzanita does have a timer, but only starts once the pack is at near full charge. It is also current adjustable, but seems to increase the voltage applied to the pack as the current knob is turned down.

Pak-Tracker is a waste.
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Old 08-11-2010, 08:51 PM
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Default Re: Killing Lead Acid batteries

That really sucks, sorry to hear it. Thanks for posting your experiences though, hopefully it will let someone else learn from your hard-knocks lesson.
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Old 08-12-2010, 02:48 AM
SimonRafferty SimonRafferty is offline
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Default Re: Killing Lead Acid batteries

It's interesting how many Lead Acid tales of woe seem to relate as much to the charger that the batteries!

Although Lithium is a great technology - it's just as much a can of worms if you don't get the charging and monitoring right.

I've been using PbA batteries every day for 16 Months now and have about 400 charge cycles on them with 50% DOD. My batteries were bought as scrap for 3 each and, if anything have improved through having a proper, managed charge cycle. My range is now 15% greater than it was on day one.

I don't think there is anything wrong with PbA - they are a good solution for many where the range can be low and cost has to be low.

If I were you, I would invest in a better charger. Best of all would be a charger that will charge both PbA and Lithium - at least then you keep your options open.

Si
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Old 08-12-2010, 12:45 PM
Duxuk Duxuk is offline
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Default Re: Killing Lead Acid batteries

have an Elcon PFC 1500 which seems OK after about 100 charge cycles. I do, however, find that I need to occasionally charge some of the six batteries individually using my nominal 12V Ctek charger. This keeps the resting voltages much closer to each other, which must be good. My range has fallen after 650 miles. It is as if the Peukert constant has increased. I have also noticed more voltage drop under load now than I had in the early days.

I don't think I did my pack any favours early on by running it down to virtually flat in a number of hour long drives.

I would advise anyone with a new LA pack to be very carefull and never run it down too far.

I'm sure I read this same advice before I was on the road but naturally ignored it!

As for your pack I don't know if you could drain all the acid and replace it completely?????????????

At least you would then have the same SG in each cell.

Andrew.
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