New batteries but low voltage

[wayne.b]

Originally Posted by sailorboy1

I had been getting up in the morning with battery voltage of 12.2 with 60-90AH out. So since the batteries were 6 years old and I had abused them I replaced them yesterday with 4 new Trojan T105s

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In my experience that's actually pretty good for 6 year old batteries. My last set of batteries were going as low as 11.5 overnight before I replaced them. You might need to give the new batteries an equalizing charge to get all of the cells on the same page so to speak, but I'd wait a while longer until you've gone through a few more charge/discharge cycles.

For what it's worth, here's a link to a product that I've had good luck with for improving battery cable connectivity:

CP8-TB Thomas & Betts Kopr-Shield Compound, 8-Oz

[Carib61]

Have you checked the draw when you are on off shore power, you might have something pulling too much amperage.

[seabreez]

Originally Posted by sailorboy1

I had been getting up in the morning with battery voltage of 12.2 with 60-90AH out. So since the batteries were 6 years old and I had abused them I replaced them yesterday with 4 new Trojan T105s that I charged till they accepted 9A at 14.4V. To test them I turned off shore power and went to bed. This morning they were reading 12.25V at -6.3A and -67 AH. This seems way too low based on the AH and is the same as the old batteries.

You are really trying to invent a new way of testing batteries or trying to convince yourself that there is a different way of testing batteries. The only way is to load test a battery to confirm the condition of the battery and to separate the good from the no good batteries. When you try and compare readings and compare .1 of a volt or so... this could lead to a dirty connection or improper tester. To then check connections do a voltage drop test. Then you properly test all connections. Once this is done, then live, use it!

[sailorboy1]

Originally Posted by wayne.b

===

In my experience that's actually pretty good for 6 year old batteries. My last set of batteries were going as low as 11.5 overnight before I replaced them.

Maybe yes, maybe no. Voltage means nothing without knowing the AH rating. For my old batteries the -60-90AH should have been 12-20% of capacity depending on the rate of discharge. For the voltage to be 12.2V means the batteries were at half capacity.

[Wood]

@Sailorboy

When you ran the hard discharge with the heater - what was the rate of discharge vis battery rated capacity @ temp?

Do you use a good hydrometer to assess SOC?

[sailorboy1]

Originally Posted by Wood

@Sailorboy

When you ran the overnight discharge with the heater - what was the rate of discharge vis battery rated capacity @ temp?

Do you use a good hydrometer to assess SOC?

I did that discharge this morning and did it hard at around 90 amps because I could only use what I had to load it. I have a hydrometer but didn't take any measurements.

I've got shore power off and have loads on to waste power to see how it looks tonight. But either way tomorrow morning I am moving on my travels.

[Wood]

My qualification is not w/ flooded LA batteries - but Trojan discharge data indicates 90A is pretty stiff. This is two bank @ 12v? So @ 12.35v you'd be at < 70% charge. I think a slower draw down - maybe C20 - would suite battery break in better.

My experience is with wet cell NiCad - which is a very different animal. But I know them well. And, no, I wouldn't consider them appropriate for marine use.

[thomm225]

Another option is just to have your batteries tested before replacing........

That's what most of the single little old ladies do around here

But I know tech types and they believe they have to figure it out for themselves ............

[Cheechako]

They should read maybe 12.45 after sitting all night no load. Maybe you have a minor load somewhere? A clock on a couple things like a stereo? Anchor light?etc.

[markwesti]

We bought a pair of T105's beginning this summer . I wasn't real happy with the way they were charging up , bout the most I could get them to after no charge for 6 hrs. was about 12.5 V . When I bought the batts. I got a little manual so I started reading it (haha when all else fails) this manual was printed by Trojan and it says batts. must be cycled 50 to 100 times before they will get to 100% SOC . Also in this manual it says batts. are 100% SOC at 12.7 V . I called the Trojan help line and the guy told me that I needed a 30 amp charger to get to full charge . I don't think he fully understood what my application was , I have been told by several people that my 10 amp charger is fine as long as I don't expect a full charge for at least 24 hrs.

[Jim Cate]

Originally Posted by thomm225

Another option is just to have your batteries tested before replacing........

That's what most of the single little old ladies do around here

But I know tech types and they believe they have to figure it out for themselves ............

Nope, not a "tech type" issue at all, it is a "cruising type" issue. How do you expect SB to "just have his batteries tested"? He's only in a marina for a short stay, he has no transport for 300 lbs of batteries, no known place that can actually do a competent test, nor the time to wait while they do it, during which time he has no battery bank on board.

Other full time cruisers will understand...

And SB, I really think your problem is related to not being fullly charged. As others have posted, the charging regime for T-105s requires higher voltages. You will never achieve fulll charge at 14.4 volts.

Jim

[thomm225]

Originally Posted by Jim Cate

Nope, not a "tech type" issue at all, it is a "cruising type" issue. How do you expect SB to "just have his batteries tested"? He's only in a marina for a short stay, he has no transport for 300 lbs of batteries, no known place that can actually do a competent test, nor the time to wait while they do it, during which time he has no battery bank on board.

Other full time cruisers will understand...

And SB, I really think your problem is related to not being fullly charged. As others have posted, the charging regime for T-105s requires higher voltages. You will never achieve fulll charge at 14.4 volts.

Jim

Why is SB1 in such a big hurry that he cannot have his batteries tested? Is he racing?

You don't have to be a cruiser to know about batteries. My battery was low for 2 months, but I still got by with it. It's a tech thing

If being at the marina is a money problem, he could anchor out and bring the batteries in one at a time etc and have them tested.

I'd anchor out and bring them in using my kayak and paddle to the nearest facility. Camping out along the way if necessary since there is no hurry when cruising

This is the difference in some cruisers.............are you cruising on a sailboat or living on a condo that floats on the water with all the nice things you have at home

[a64pilot]

OK, I'm in Panama City Fl.
Where would I take batteries to be tested?

[Jim Cate]

[QUOTE]I'd anchor out and bring them in using my kayak and paddle to the nearest facility. Camping out along the way if necessary since there is no hurry when cruising
[/QUOTE

Ho,ho,ho!

Funniest post in a long time...

Paddle to the nearest facility... right! The valet parking attendant at the dinghy dock might even help you carry the batteries up to the service bay...

Doesn't seem like reality to me, but perhaps SB will take your advice.

Jim

[thomm225]

Originally Posted by a64pilot

OK, I'm in Panama City Fl.
Where would I take batteries to be tested?

Ask any little old lady?

AutoZone in Panama City, FL | 11600 Panama City Beach Pkwy.

I've also sailed in Panama City. Did the shell island race. Not a problem to get a battery tested.

I also did multiple races buoy races from that park by the highway 98 bridge. The old one and the new one