Thin plate AGM batteries vs. flooded deep cycle batteries

Black_Diamond

Bit the bullet yesterday, stayed with the 24M for starting, moved up to the 31M for the house batteries.  Hoping the years of life make up for the cost!

J3ff

So I went with two of these:  http://www.homedepot.com/p/Nautilus-31-Deep-Cycle-Marine-Battery-31MDC/205309650  for the house. They seemed to be the most power for the buck... is the only thing better here that the thin plate agm will accept more of a charge and charge back up faster? 

Handymans342

Black_Diamond said:

Bit the bullet yesterday, stayed with the 24M for starting, moved up to the 31M for the house batteries.  Hoping the years of life make up for the cost!

Did you have to change the boxes?

Black_Diamond

Starting battery 24M: same battery.
House Batteries (going from 27M to 31M) the battery box fit the 31 too.

No changes.  for once!

craigswardmtb

Earlier this week I changed all my batteries in the engine room to Group 31 AGM's.  I had to swap out two Group 24 battery boxes.  I already had two Group 31 boxes in there.  That project sucked a bit more than expected.  You forget how heavy those things are.  And they are tucked away in the starboard aft area of the engine compartment on my 360.  Not too fun, but i'm looking forward to the increased performance as we spend a ton of time on the hook.  Boating season is almost here.  19 days to launch and counting!

LaRea

@Black_Diamond - impressions of the TPPL so far?  My house bank is toast, so I'm shopping batteries.

Black_Diamond

So far ok. Only been in the water 10 days tho.  lol. 

ChesapeakeChiller

@LaRea I went with 2 of the Northstar TPPL AGM's for house battery's as well. So far I am happy with them (day trips) but I have not spent the weekend out yet to really see the benefit of longer lasting/faster recharge.

Dream_Inn

I have the same tools and testing them on the hook right now. So far I'm happy, but next weekend I'll yes them out for a couple nights.

LaRea

I brought home two Northstar group 31 TPPLs today.  First impression - they are HEAVY!  They weigh 76 lbs, compared to 60 for flooded.  Believe me, I noticed the difference while hefting those things over the water heater into their trays.

@Dream_Inn - I'll be testing mine next weekend too!

LaRea

Man, those TPPLs really outperformed any battery I've ever had.

Here's my totally un-scientific proof:  while anchored out this weekend, the house batteries lasted so long that the ice in my ice-maker started to melt.  In the past, that never happened.  The batteries would run low, so I'd fire up the generator for a couple hours, which would chill the ice-maker.  Now, the batteries last longer and the recharge cycle is shorter.

Michael T

@LaRea - that is exactly the experience that friends have had and that I reported on the forum before. Two cautions that friends have mentioned is to fully charge them before draining them (series 31 can be discharged to 80% about 400 times) and to make sure your battery charger is capable of charging them properly. From what I have heard Northstar and Mastervolt make the best TPPLs. Friends have reported super fast recharge cycles that support TPPL claims of 300% or faster Ah charging. Self discharge rate is exceptional at 1% or less per month. Engine cranking is the best at over 1000 MCA for a series 24 up to 1500MCA for a series 31. Yes, they are a lot heavier that is because of the extra plates due to their thickness (actually thinness lol). The lead plates are rolled not cast.

Dream_Inn

Yes, mine seemed to perform very well.  The last night anchored out, I hadn't ran the genny, and didn't need to start it in the morning, just waited until we were leaving and let the engines charge them back up on the way home.  The biggest thing I did notice was just a couple hours of the generator and they went back to full charge.

davidbrooks

So i know i need to start replacing batteries and if $$$ wasn't an issue i would very likely just go get the Northstar's.  Currently i have a mix of Interstate 24 series for starting and 27's for the house.  If i turn the engine off the amp dies almost immediately.  But from what i have read the AGM's are pretty particular with the charging requirements vs older batteries.  This would mean that i would possibly need to change out both alternators and battery charger.  The charger is the Intelli Marine PD2040. So i keep going back to the Sams Club Duracell 31DTMAGM for $179.   Did you all change out or upgrade your alternators and charger?  

Dream_Inn

I changed out my charger a while back, but I did not do anything with my alternators.  Honestly, a good flooded group 29 or 31 deep cycle will probably do you just fine (actually two tied in parallel for your house).

frodo13056

Been following this thread and did not see any comments regarding off season storage - improper storage will greatly reduce the life expectancy of ANY type battery.
I have stuck with the wet cell (flooded lead acid batteries- 27's for the house and 24's for starting) since my boat was new (2008 320) and I am currently 4 years into my 2nd set of house and starting batteries. First set got me through 5 years of boating but we don't spend a lot of time on the hook - maybe 12 hours max and have never over-nighted.
Originally, I used to remove all 4 batteries during storage and used a trickle / maintain type charger. That got old after the first 3 seasons and where I store now (indoor semi-heated), I just plug the boat in and let the on-board charger do it's thing. Pre-season checks show the current batteries are in good shape.

Michael T

I would not say that AGMs are "particular" any more than any other brand. The most important thing to remember is that different battery chemistries have to be charged according to their needs - which often don't vary much and most newer chargers will accommodate. I have never heard of a need to replace alternators when up-grading to AGM or TPPL

IMO deep cycle flooded and flooded starter are beyond yesterday's news. They're anchor material. Recent AGMs and certainly TPPLs have plenty of starting power for even today's most demanding engines. I had, at the time (2014) the most advanced Rinker EC 360 that had ever left the Rinker factory, with twin 502s, Axius, DTS, Bluetooth and WiFi electronics. Even with the Axius demand for clean power there was plenty available using Series 31 AGMs.

With the proper battery cabling - that we have discussed on here - a set-up that significantly lengthens the reserve minutes and draw-down you can still achieve far greater power by going from 2 to three house batteries. Power gains with properly cabled AGM and better yet TPPL are exponentially (not arithmetically) derived with every house battery you add above two. I had three series 31 AGMs and their reserve power smoked any of the guys with deep cycles.

For several years the AGMs have proved that they will perform very well as starting batteries and (except for TPPLs) are absolutely unbeatable for house batteries.

So, if re-powering with batteries you can keep all of your batteries the same chemistry AGM or TPPL.

If your at anchor needs are less demanding the old fashioned technology of flooded will be fine. If you want super fast re-charging, many more draw-downs, huge battery synergy (particularly by adding a third house battery) then go with the newer technology.

Again - NB, NB, NB - cable them properly to almost double the reserve minutes and AH of your house bank.

davidbrooks

Thanks Guys.  What got me thinking about the alternators was that i was trying to read up on all the facets and figure out if my 2003 would handle it or if i was just buying nice batteries and then treating them badly with old charging technology.  For instance several sites state that: 

Battery Charging: Remember, you must put back the energy you use immediately. If you don't, the battery sulfates, which will affect performance and longevity. The alternator is a battery charger. It works well if the battery is not deeply discharged. The alternator tends to overcharge batteries that are very low and the overcharge can damage batteries. In fact, an engine-starting battery on average has only about 10 deep cycles available when recharged by an alternator. Batteries like to be charged in a certain way, especially when they have been deeply discharged. This type of charging is called 3-step regulated charging. Please note that only special smart battery chargers using computer technology can perform 3-step charging techniques. You don't find these types of chargers in parts stores or big box stores.

 

1. The first step is bulk charging, where up to 80% of the battery energy capacity is replaced by the charger at the maximum voltage and current amp rating of the charger.
2. When the battery voltage reaches 14.4 volts this begins the absorption charge step. This is where the voltage is held at a constant 14.4 volts and the current (amps) declines until the battery is 98% charged.
3. Next comes the Float Step. This is a regulated voltage of not more than 13.4 volts and usually less than 1 amp of current. This in time will bring the battery to 100% charged or close to it. The float charge will not boil or heat batteries, but it will maintain the batteries at 100% readiness and prevent cycling during long term inactivity. Note: Some gel cell and AGM batteries may require special settings or chargers.

This was pulled from https://www.batterystuff.com/kb/articles/battery-articles/battery-basics.html Also there was an interesting comment on another forum where a guy was asking the same question that i was ( http://www.sailnet.com/forums/electrical-systems/197921-northstar-vs-odyssey-tppl-agm-batteries.html) the response stated that: 

For either battery your stock alternator is woefully inadequate for giving these batteries the charging they desire & need. Odyssey wants a minimum of .4C in charge current (40A for a 100Ah battery) and suggest 14.7V absorption for the longest cycle life. Northstar simply suggests that the more current the better. They suggest 14.5V but in a marine application these batteries, just like the Odyssey, will do better at 14.6V -14.7V. The Northstar guidance is conservative and broad based for all applications. For marine either battery will do best at .4C and 14.6 - 14.7V then the proper float voltage... A stock Hitachi can't even come close to doing these batteries any justice...

Before you spend money on TPPL AGM batteries you will ideally want to address the rest of the system first....

I agree that the technology has come a long way... Just don't want to toss in great technology just to have it last as long as older stuff cause i didn't have the requisite components to keep it maintained.

Dream_Inn

I really think the question you are trying to come to a conclusion on is "is it worth the extra cost?".  This spring I just purchased 4 new batteries (on sale for 30 or 40% off & an extra 10% back in WM points) that still cost me close to $1100.  Two Northstar and two of their best starting AGM.  I really didn't need the fancier starting batteries, but the price wasn't bad and since I was switching to TPPL AGMs for house, what the heck!  I do have the promariner charger that should handle it all quite well.

Until now, I've made it on the Wal-Mart Everstart group 29s (yep for $100 ea) with no problems!  Lasted me 5 full seasons on my 400!  & let me tell you, I anchor out a lot!  My starter batteries....get this, they were original until this spring.  (Flooded starting batteries that were installed in the boat in 2007, lasting almost 10 years!!)

LaRea

I just installed a new charging system to handle the TPPLs.  See the thread here:

http://rinkerboats.vanillaforums.com/discussion/7291/new-ttpl-batteries-plus-blue-sea-systems-charger-and-battery-monitor

To answer the question about "is it worth it" ... it's all about how much time you spend anchored.  

Lots of people never run their house batteries more than a couple hours, so TPPL would be a waste of money for them.  Not me.  I spend a lot of time anchored, with lots of overnighters, so it's definitely worth it for me.  I hate running the generator because of the noise, and I love having power for the conveniences.