Can someone interpret these battery readings?

[shortspark]

In another thread I talked about the problems I have had with my 2006 CC Precedent. I don't want to hijack that thread further so I'll ask my question here. I have the four 12v system that everyone knows is not a good one for batteries. Like most everyone else that has one of these carts, I had my batteries (Trojan) replaced under warranty. Mine were at the four year cut off point when they were replaced by US Battery, which CC now uses. I guess Trojan was sick and tired of having to replace these batteries within the four year warranty period but, from what I hear, US Batteries are very good. The dealer also replaced the OBC at the same time, also under warranty. All this took place in January 2010.

Lately my amber charge notice light has came on before completing a round of golf. The dealer initially said the batteries were going bad but now he is saying that they appear to be okay and may have been affected by the unusually cold weather we've had. During that time I charged them every two weeks anyway. I have the chart that shows the percent of charge for the various battery volts but the tests the dealer conducted are cell by cell so I don't know if I have to do averages or high/low or what. Could someone tell me if I'm okay for one year old batteries based on these figures? Once again, the batteries are date coded AOX which I assume means Jan. 2010.

Battery One Before Charge: Discharge minutes/voltage = 67 min. @ 10.68v
cell 1 - 11.25
cell 2 - 11.10
cell 3 - 11.20
cell 4 - 11.10
cell 5 - 11.25
cell 6 - 11.20

Battery One After Charge:
cell 1 - 12.75
cell 2 - 12.70
cell 3 - 12.50
cell 4 - 12.50
cell 5 - 12.75
cell 6 - 12.75

Battery Two Before Charge: Discharge minutes/voltage = 67 min. @ 10.52v
cell 1 - 11.10
cell 2 - 11.05
cell 3 - 11.00
cell 4 - 11.10
cell 5 - 11.00
cell 6 - 11.05

Battery Two After Charge:
cell 1 - 12.70
cell 2 - 12.65
cell 3 - 12.70
cell 4 - 12.60
cell 5 - 12.55
cell 6 - 12.60

Battery Three Before Charge: Discharge minutes/voltage = 67 min. @ 10.40v
cell 1 - 11.10
cell 2 - 11.00
cell 3 - 11.05
cell 4 - 11.10
cell 5 - 10.90
cell 6 - 11.90

Battery Three After Charge:
cell 1 - 12.55
cell 2 - 12.60
cell 3 - 12.75
cell 4 - 12.70
cell 5 - 12.70
cell 6 - 12.60

Battery Four Before Charge: Discharge minutes/voltage = 67 min. @ 10.40v
cell 1 - 10.90
cell 2 - 11.00
cell 3 - 11.05
cell 4 - 11.10
cell 5 - 11.05
cell 6 - 11.09

Battery Four After Charge:
cell 1 - 12.55
cell 2 - 12.60
cell 3 - 12.50
cell 4 - 12.70
cell 5 - 12.65
cell 6 - 12.60

Everything seems consistent at least. I am not sure if I am suppose to take the after charge average of the cells in each battery to determine the charge or what. If that is how the battery condition is measured then according to the state of charge table I guess I am fine. However, after I play my next round of golf and charge it up myself, I will take a reading of each battery. All these readings were done by the dealer at the request of US Battery whom I contacted personally.

So, what do you guys read from all this considering these US Batteries are a year old and I play my course about three times a week average?

[Golfdog]

Seems to be some confusion. A 12v battery has 6 cells, each of which is 2 volts. Not sure where 12v per cell comes from

[shortspark]

Originally Posted by Golfdog

Seems to be some confusion. A 12v battery has 6 cells, each of which is 2 volts. Not sure where 12v per cell comes from

Hum, come to think about it I guess you are right. How can a 12v battery have more than that amount per cell? The figures above came from the work sheet the dealer gave me. I guess I should ask him about it and how he could possibly have come up with these figures.

[scottyb]

LOL. They are specific Gravity readings and you may have a problem, A discharge test of 67 minutes is less than 70% capacity. And readings of 10.90 and 11.00 are 20% specific gravity. For 1 yr old batteryies these readings are low. Re-check the charger and the OBC. Check the charge cycle end voltage, let the batteries settle 12 to 16 hours and recheck batteries. How many recharge cycles do these batteries have on them?

[shortspark]

Originally Posted by scottyb

LOL. They are specific Gravity readings and you may have a problem, A discharge test of 67 minutes is less than 70% capacity. And readings of 10.90 and 11.00 are 20% specific gravity. For 1 yr old batteryies these readings are low. Re-check the charger and the OBC. Check the charge cycle end voltage, let the batteries settle 12 to 16 hours and recheck batteries. How many recharge cycles do these batteries have on them?

Thanks Scottyb. I don't even know what "specific gravity" is but yes, it is mentioned on the work sheet that these are specific gravity measurements. I just wrote US Battery an email and included these measurements. I want them to tell me if the batteries are "okay" as the dealer said, or if they think there is a problem as you do. I'll report back here what US Battery says.

[scottyb]

I think you need more testing to determine if there is a problem with the batteries or OBC

[shortspark]

Originally Posted by scottyb

I think you need more testing to determine if there is a problem with the batteries or OBC

Yes, I've got my own volt meter so I'll test the heck out of them, after a round, before a round when full charged, right after a charge, and after having them sit for a while. I'll test them individually and as a pack.

I got a quick response from US Battery. I gave them the figures in this thread that the dealer came up with and also mentioned someone at a cart forum (that someone being you but not by name) said the readings were low for one year old batteries and I might be in trouble. The US Battery technician said your recommendations of testing the obc and charger were good ones but he did not believe the batteries were bad based on these numbers.

In a nut shell, he said that the obc puts in to a battery only that what was taken out of it - 1:1. That meant that battery equalization becomes all that much more important (in fact, the CC dealer indicated the battery numbers actually got better as he topped off each time). Further, the US Battery technician said the readings were consistent and show no major problem at all. A battery reading of 70% is healthy and although the specific gravity readings may be a little low that does not mean the battery is bad. He said a battery is either good or bad with the percent of "good" being directly linked to charging cycle and depth of discharge.

He is recommending equalization more often than usual with a "top" off of charge about once a week. He said simply wait until the charger has completed its charge, pull the plug from the cart for ten seconds and then reinsert it. This "top off" charge could even run an additional hour. I never did an equalization in all the years I've owned carts - and every one has been electric. But, you learn something everyday. Hopefully I will get a few more years out of these things.

Oh, I need to edit this to ask you a quick question. What is the difference between a Power Drive 2 and a Power Drive 3 charger?

[sonicj]

Originally Posted by shortspark

In a nut shell, he said that the obc puts in to a battery only that what was taken out of it - 1:1. That meant that battery equalization becomes all that much more important (in fact, the CC dealer indicated the battery numbers actually got better as he topped off each time). Further, the US Battery technician said the readings were consistent and show no major problem at all. A battery reading of 70% is healthy and although the specific gravity readings may be a little low that does not mean the battery is bad. He said a battery is either good or bad with the percent of "good" being directly linked to charging cycle and depth of discharge.

He is recommending equalization more often than usual with a "top" off of charge about once a week. He said simply wait until the charger has completed its charge, pull the plug from the cart for ten seconds and then reinsert it. This "top off" charge could even run an additional hour. I never did an equalization in all the years I've owned carts - and every one has been electric. But, you learn something everyday. Hopefully I will get a few more years out of these things.

your obc will initiate a equalization routine on its own, usually when it detects a fault. ie: soc voltage doesn't match up with Ah consumed. its not something you would ever notice unless you pay close attention to the amp meter on the charger and the elapsed time. the us battery technician is having you force a equalization charge which is a good idea imo. after that, get 4 or 5 regular uninterrupted discharge / charge cycles on the cart and see if that doesn't clear things up.

[shortspark]

Thanks for that sonicj but I am unclear what you meant by "get four or five uninterrupted discharge/charge cycles on the cart..." What does that mean and how do I achieve it?

[GLEEMO]

looks to me like the only thing U can tell from this is U took the cart to the dealer,
at 60% to 70% charged.
The dealer charged it to about 95% of charge.
As for getting to 100% the batteries may not be broken in yet since it takes over +100
charges to get to that state.

Charging every 2 weeks as stated = 30 to 35 charges at best.