[wayne c]

Hello everyone. I am new to the EV world, and I just completed my conversion. My car is a 1988 Ford Escort EXP, 144v system and I love to drive it.

I am a little concerned with the way the batteries are charging, and I thought I would ask some of the experts on this forum.

Question #1 while charging, should all the batteries charge at the same rate, or is it OK to have a 10-15 point spread as they charge as long as they top off about the same (within 5-10 points of each other).

Q#2 My pack is 12-12v Trojan T-1275 batteries. During the gassing stage, between 80 & 100 % of charge they will reach 196 v. Is this normal? The resting volts 24 hours after charge is around 156 v.

Finally, my charger is an El con PFC300 and it flashes a code that says I should " repair battery". It will do this just before going to 80% charge, and then continue on normally. EV America, where I bought the charger, says not to worry about it, that they have received information about other PFC3000 doing the same thing. Anyone of you using this charger, and what can you tell me about it? Also, the equalizing is built into this charger according to El Con. Is that a good thing or not?

Sorry for the long post, but like I said I am new and learning.
Thanks for any help, Wayne

[bblocher]

Originally Posted by wayne c

Question #1 while charging, should all the batteries charge at the same rate, or is it OK to have a 10-15 point spread as they charge as long as they top off about the same (within 5-10 points of each other).

I'm not sure what you mean by points, but it is normal to see batteries charge at different rates.

Originally Posted by wayne c

Q#2 My pack is 12-12v Trojan T-1275 batteries. During the gassing stage, between 80 & 100 % of charge they will reach 196 v. Is this normal? The resting volts 24 hours after charge is around 156 v.

It does depend on your temperature, but that voltage is way too high. You'll want about 14.7v peak in the summer and maybe 15.1v or so in the winter. Check for a chart showing the exact manufactures specs for charging vs temperature for your batteries. Resting voltage fully charged should be about 12.8v. The 13v you're seeing isn't suprising since they are getting over charged so much, but you're shaving off some life on the batteries. Again most importantly, find the exact manufacturer specs for charging vs temp.

The pulsing charging is good, but you really should invest in a balancing system. They will do a better job and keep batteries in the proper ranges.

[Zemmo]

I'm not expert but I can help out some.

Every battery will be slightly different, even ones that came off the same production line. But they will be close to the same voltage and capacity. So it won't be too unusual that you might be one 10th of a volt off between your batteries (12.9 and 12.8). If the batteries start to be different by a few 10th of a volt, then thats a sign of something. Possible low fluids, needs an extra charge to finish charging, etc. But in general, the batteries should be close, as the pack ages the differences will get a little more and more as it ages.


Your charged out voltage of 196 while on the charge, it too high (I think). Depending on the battery, most people say about 2.4 volts per cell (general rule of thumb). By that number your pack voltage should be closer to 177 volts (72 cells X 2.4 volts).

Your resting voltage sounds right at 156 volts (on a good healthy battery pack, an older battery pack would slow get lower and lower). So your resting voltage sounds fine.

Don't know about the charger so i'm not much help there. But if the battery charger things there is a problem.... I would say chances are, there is. Maybe it has the wrong battery profile loaded on it? It could be trying a Lithium Battery profile on a Lead Acid battery. Don't know, those are just guesses.

I hope some of this info helped.

[DIYguy]

regarding the charger... I have the 6kw version of the same brand. I have no experience with it yet...but you need to ensure that you have the correct algorithm loaded for your batteries. The charger holds 10 such charge profiles. You are able to select any one of these ten ( I can help with the procedure if you need help)...but if your battery requirement is not the right one and it is not one of the ten, you will have to get it reprogrammed. Did you get a sheet with charge profiles listed on it. Greg frm Elcon says that his units come with such a sheet and EVA should have passed that on with the charger.

cheers,
Gary

[wayne c]

Gary. EVA did send the sheet with the profile loaded. It was programed by Elcon for my battery pack. I called them the other day and was told that according to Trojan, my batteries can charge up to 2.8v per cell. That would mean with 72 cells it could go over 200 volts if they are right. That just seams extremely high to me. I am going to send Tech support at Trojan an email to get it straight from the horses mouth.

I currently have #5 loaded in the charger according to Elcon. They told me that I could put #4 in, but I would have to turn it back up when the batteries gets older.
If you have instructions for changing the settings, please email them to me at waynec49@hughes.net Thanks for your help, Wayne

[wayne c]

Brian, Like I said in my post I am new to EV's, so what is a balancing system and what system would work the best with the 144v Trojan T-1275 batteries?

Thanks, Wayne

[wayne c]

Zemmo, the batteries have always shown a few 10th difference after a full charge, up to 5 or 6 10th on a few of them. I have only had them about a month.

Elcon, the charger manufacturer, says that the equalization charge is built into the charger. Have you ever heard of that? If that is true, do you have a suggestion how I can get the batteries closer together.
Thanks, Wayne

[DIYguy]

Originally Posted by wayne c

Zemmo, the batteries have always shown a few 10th difference after a full charge, up to 5 or 6 10th on a few of them. I have only had them about a month.

Elcon, the charger manufacturer, says that the equalization charge is built into the charger. Have you ever heard of that? If that is true, do you have a suggestion how I can get the batteries closer together.
Thanks, Wayne

Balancing refers to adding some kind of intelligent device (some more intelligent than others) to help in equalizing the charge. When charging multiple batteries in series, the charger doesn't know if one of them is slightly more or less charged. A balancing circuit may be used across the terminals of each battery which disipates energy as heat (or in some cases passes this energy on to other batteries less charged) until the charging is complete. Often, the balancing is more active the first few times it's used, and after that plays less of a role unless some other influencing even takes place.

I think in this case, Elcon is a distributor as your charger is likely made in China.

Good idea to go back to Trojan to find out more details related to your batteries.

BTW, the "VoltBlocher" is one such basic but good value balancer. (I bought them for my AGM's .... which is more of an issue than with floodies)

[DIYguy]

here is file that describes the procedure for changing profiles......