Community Forums

Lug_Nut · 06-26-2010, 07:35 PM

I stand corrected on their stance on equalizing, it is now in writting. Believe me, it seems every supplier and agent have a different story. I use Discovery and also LifeLine in my boat and Discovery in my coach.

Peter

RJay · 06-26-2010, 08:09 PM

It's very conceivable if the battery is put into an equalizing charge before the battery has been fully charged, the internal resistance could produce a voltage that adds to the already high equalizing voltage and possibly damaging the battery. But Lifeline is specific about the battery's state of charge before equalizing.

LindyT · 06-27-2010, 12:09 AM

My best (only) guess, this mystery relay involves a trickle charge to the chassis batteries. If someone finds out, I'd be curious.

I plan on replacing my 6 house batteries with AGM before they rust through the tray.

Lug_Nut · 06-27-2010, 03:59 AM

Interestingly enough, I just looked up Discovery AGM battery's website. It states DO NOT EQUALIZE THEIR AGM BATTERY, under a warning.
I have Discovery in my coach. Newmar installed mine as I believe they mainly use Discovery. The jury could still be out on this.

Peter

RJay · 06-27-2010, 03:41 PM

Peter,

Is the name of the battery you're referring to "Discover" or "Discovery"?

Lug_Nut · 06-27-2010, 03:44 PM

Sorry, yes it is Discover.

Peter

Dav5942 · 06-27-2010, 03:56 PM

Canadian company-not a whole lot of exposure in the US. Don't know why they have a problem equalizing.

Lug_Nut · 06-27-2010, 04:10 PM

Well it may not be the largest company or the most experienced either, but it is what Newmar installed, and possibly is still. But, even LifeLine says equalizing should be conditioning and only advises it if the batteries have lost performance. They also say that this method of conditioning was thought wrong not long ago. This would indicate much you hear may vary widely.
I would be very cautious about such charging at this time. Mind you I have a total of over $15,000 spent on this technology.
Interestingly I had two units replaced by Optima on warranty due to not holding a charge. This was last March. Their service rep. was twice to the boat. At no time was equalizing mentioned as a possible fix.

Peter

wa8yxm · 06-27-2010, 04:25 PM

RE Equalizing: AGM batteries are not supposed to need this as often as flooded wet cells. HOWEVER:

IF the batteries are "Showing signs of capacity loss" (Read that nearing end of life) you are looking at a situtation where It might help.. It might not, but even if it hurts you are basically no worse off then you were eight hours ago when you pressed the EQULIZE button.. That is to say on the way to the battery store.

My question is why everybody is so hot for AGM's.. I mean they are way more expensive and the only practical advantage I can find is the mount at odd angles, no "This Side Up". True lifelines can charge much faster but in the overall scheme of things the saved time will be perhaps 10-15% of the total charge time.. Since this only affects BULK charge, not absorption.

Dav5942 · 06-27-2010, 04:52 PM

Over 20 years on the boat, had no problem with convential batteries(did have one blowup, no damage just scared everyone on the dock)-even ones purchased in Venezuela, while fishing for Blue Marlin, lasted over ten years with no problems. However over the last four years with coach have been fighting out gasing problem. No overcharging, no over filling, tried special caps that helped for a while, etc. Found AGMs from a friend who owns Lifeline at the Miami boat show and will be installing them soon. If they perform close to the convential batteries we will be happy to have gotten rid of the maintenance problem.

Lug_Nut · 06-27-2010, 05:45 PM

Quote:

Originally Posted by wa8yxm

RE Equalizing: AGM batteries are not supposed to need this as often as flooded wet cells. HOWEVER:

IF the batteries are "Showing signs of capacity loss" (Read that nearing end of life) you are looking at a situtation where It might help.. It might not, but even if it hurts you are basically no worse off then you were eight hours ago when you pressed the EQULIZE button.. That is to say on the way to the battery store.

My question is why everybody is so hot for AGM's.. I mean they are way more expensive and the only practical advantage I can find is the mount at odd angles, no "This Side Up". True lifelines can charge much faster but in the overall scheme of things the saved time will be perhaps 10-15% of the total charge time.. Since this only affects BULK charge, not absorption.

Well as stated, they are cleaner. I owned two Newmars prior to the one I have now. No issue with the others. I maintained them well and did not mind doing so, as often as needed. My current coach is an all electric. Oh Boy! Talk about corrosion, no matter whether your cleaned and serviced them every two weeks. I even tried the mineral oil, some help but still real bad. With the AGM's absolutely no mess. I love it. Whether they last longer, we will see.

On my boat I have 5 banks made up of large battery groups. The aft utility bank is accessed through a hatch in the swim plateform. Required removing a cover while hanging upside down, Checking and filling is just a little worse than the acrobatics. The forward utility bank is accessed by removing a carpet in a forward stateroom, opening a hatch in the sole, removing a cover, etc. Similar skills needed as aft. The house bank is located beneath an aluminum plate that is bolted down in the engine room. However, you first must remove 4 huge engine batteries to access the cover plate. Need I say more on those? The engine batteries are easy, hurray!!! Obviously the lack of need for maintainance is key. Additionally corrosion is an issue, but not with the AGM's. You could eat off them.
I would never go back to wet cells in these applications.

Peter

EngineerMike · 06-27-2010, 05:57 PM

In my mind the maintenance issue is the key benefit. AGMs should reliably last about 8 years (assume proper charging). Out of the bank of 6 U2200's (660AH) previously in my current coach, two of them continually had gassing problems, and caused a mess; I tried all different charge parameters but no change. At less than 3 years they were exhibiting low charge problems, and would "float" at ~15amps. I would have gotten 4 years max, and put up w/the mess the whole time. The AGMs I have now float at 0-3amps, have been in 4 months and are as squeaky clean as the day I scrubbed the tray & zip-tied them in place, and they float at 0-3amps like when new.

I have a theory about the current crop of lead acid- if you buy Trojan you can probably get great quality controlled lead plates, but if your batteries are competitively priced you get what you get in lead composition, and impurities or variation in the sponge lead cause differences in charging between plates that you can never escape. Just a theory as to why one or two batteries in a string make a giant mess and the others stay clean and don't constantly gas.

LindyT · 06-27-2010, 06:45 PM

I had U2200's in my last coach - never an outgassing problem and I averaged 6yrs out of them. The Newmar (all electric) is on its second set and two of the six batteries are bulging (slightly) already, not to mention making an enormous mess of the battery compartment. Maintained, never run down (in fact, we're usually either connected to shore power or running the genset.) I think CorporateMonkey is right - there is something amiss with the 6V system.

I'm not particularly excited about spending $1,600 on AGMs that SHOULD have been in there to begin with - but the wet cells are coming out ASAP. I'll probably install the mod that CorporateMonkey did.

wa8yxm · 06-27-2010, 09:43 PM

Quote:

Originally Posted by Lug_Nut

On my boat I have 5 banks made up of large battery groups. The aft utility bank is accessed through a hatch in the swim plateform. Required removing a cover while hanging upside down, Checking and filling is just a little worse than the acrobatics.

I meant to include cases where access for maintenance was an issue too. I normally do, but skipped it,, Thanks for pointing it out.

I've suffered very mild seasickness symptoms (I DID NOT loose my lunch) on two occasions.. One was one of those "MAX" theaters with a roller coaster film.. My eyes were telling me one thing and my behind another (Well actually my inner ear but behind sounds better here)

The other time was hanging upside down in the fuel hold of a small boat in choppy water.

I do agree that there are cases where a maintenance free design makes sense But again, the added cost of AGM over wet type.. I"m not so sure

I will be interested in hearing your opinion of Flooded wet, Maintnance free non-agm and AGM when you have tried all three to battery death.