New Trojan 105 Charging Issue

[Penleya]

I have a 36 volt 2006 EZGO with 6, 6 volt batteries just so everyone knows before I explain.

I had some older batteries in my cart, after doing a lot of testing on them I realized they were just not holding voltage like they used to so I decided to get new ones.

With the old batteries, the charger would charge the batteries and cut off when it was charged. The batteries would just lose too much charge within 12 hours

I put brand new Trojan 105 batteries in it today and charged them first thing like you are supposed to do before using. Before charging, the batteries read 6.33-6.35 volts each.

After about 10 hours the charger was still running. I was afraid to keep it going because I think they should be charged by now and did not want to leave it overnight.

I did hear the batteries slightly bubbling it sounded like. Immediately after pulling them off of the charger the volts were 6.38-6.39 each battery.

The charger does buzz louder than normal but I have heard this does not hurt anything. Also, the charger is a Powerwise II. Let me know if you guys have any ideas. I think it is charging correctly but just not shutting off like it should.

[Gr8hntr]

Think I read on here the first few charges or maybe just the first takes longer ... one of the pros will chime in tho

[Hecky50]

Originally Posted by Penleya

I have a 36 volt 2006 EZGO with 6, 6 volt batteries just so everyone knows before I explain.

I had some older batteries in my cart, after doing a lot of testing on them I realized they were just not holding voltage like they used to so I decided to get new ones.

With the old batteries, the charger would charge the batteries and cut off when it was charged. The batteries would just lose too much charge within 12 hours

I put brand new Trojan 105 batteries in it today and charged them first thing like you are supposed to do before using. Before charging, the batteries read 6.33-6.35 volts each.

After about 10 hours the charger was still running. I was afraid to keep it going because I think they should be charged by now and did not want to leave it overnight.

I did hear the batteries slightly bubbling it sounded like. Immediately after pulling them off of the charger the volts were 6.38-6.39 each battery.

The charger does buzz louder than normal but I have heard this does not hurt anything. Also, the charger is a Powerwise II. Let me know if you guys have any ideas. I think it is charging correctly but just not shutting off like it should.

You may want to read this , it cant't hurt...http://www.cartsunlimited.net/Batter..._Tutorial.html

[Penleya]

Thanks guys. I guess I just would like to know if this is normal for them to take a very long time to charge, even if the batteries were nearly charged to start with, and then 10 hours later still going on the charger.

I just want to be sure I do these first 10 charges or so the right way.

[DaveTM]

What is the amp rate of your current battery charger?

[JohnnieB]

The initial charge can take a very long time, even if the voltage indicates they are close to being 100% SoC.

The PW-II charger has a 16 hour back-up timer that terminates the charge if the On-Charge pack voltage does not reach about 45V within that time frame and the initial charge on some battery packs will exceed 16 hours. Most don't, but some do.

Put your new batteries back on charge and let them charge until the PW-II shuts off automatically or times out at 16 hours. If it times out, restart the charge cycle. Since you've already charged them for 10 hours, the PW-II will most likely shut off automatically rather than timing out.

You mentioned the batteries were at 6.38-6.39 volts immediately after you unplugged the charger after 10 hours. That is only about 38.3V and the PW-II will not shut off automatically until the On-Charge voltage climbs into the 44-46 volt range, so they still need several more hours of charging.

The bubbling you heard is both normal and good. It is called "Gassing" and is the result of electrolysis of the water in the electrolyte that occurs when a lead-acid battery is being charged.

Attached is the charge profile the PW-II is based on.

[Penleya]

Thanks JohnnieB! I checked them again this morning after about 10 hours off of the charger and they all read 6.41 volts. I believe they were showing well over 7 volts while charging.

I will hook the charger up today and let them go. 16 hours from now I will be in bed so hopefully it cuts off before I go to sleep.

If for some reason the charger stayed on overnight would that cause any damage to the batteries?

[JohnnieB]

Originally Posted by DaveTM

What is the amp rate of your current battery charger?

Dave brings up a very good point.

When first plugged in, the ammeter ought to climb to about 20A and stay there until the On-Charge pack voltage exceeds 40V and then decrease steadily as the voltage climbs through 42V, leveling off in the 5A to 7A range until the pack voltage climbs into the 44-46 Volt range where the charger shuts off automatically.

[Penleya]

I just plugged it in about 5 minutes ago. The meter is showing just over 0, like 2-3. It was at 20 or so yesterday when I plugged it in the first time

[JohnnieB]

Originally Posted by Penleya

Thanks JohnnieB! I checked them again this morning after about 10 hours they all read 6.41 volts. I believe they were showing well over 7 volts while charging.

I will hook the charger up today and let them go. 16 hours from now I will be in bed so hopefully it cuts off before I go to sleep.

If for some reason the charger stayed on overnight would that cause any damage to the batteries?

If the ammeter on the PW-II is reading 7A or less, they will be fine overnight, In fact, a couple days at that rate won't hurt them.

If they were over 7V (42V for the pack) they ought to be gassing pretty good, and my guess is that the charger will shut of before you go to sleep.

If the PW-II was shutting off automatically with the previous pack, it will probably shut off automatically with the new pack, but just in case, the max On-Charge voltage you want to let them climb to is 2.79VPC, which is 8.37V per battery or 50.22V for the 36V pack.