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Bemota's avatar
Bemota
Explorer
Jul 15, 2016

NorthStar battery

Thinking of replacing Exide 24 MDP that was in the FW when we got it a year ago. I replaced the Wifco charger with a PD 9260. The lights were flickering last Dec., tried two batteries in parallel and the wifco fried? both. Now with a good charger, thinking of 2 gr 27 Exide batteries or 1 NorthStar AGM31M ($4 more than the AGM27), at local battery store. I can get the NorthStar for $90 more than the 2 Exides. That's my only choices, locally without ordering in and not on sale !! What option is better I have the room, trying to cut down on weight. Snowbirding we are usually on shore power. Hunting, fishing are 3-4 days at a time boondocking a couple lights fridge and tunes, peace and quiet.
  • I have seen my digital ammeter, during engine cranking, read as high as 170 amps when coastal southern california winter cold ( not very cold) but usually this is ~120 amps overnight cold.

    When engine is warm, I see 65 to 75 amps. I think the ammeters refresh rate is about 3 to 4 times a second, and my engine rarely cranks for a full second before catching. I wish I had a clampmeter with a peak amp hold to really see.


    My point was that this Northstar battery cranks my engine faster than any other battery, or batteries in parallel, that I have used in the past.

    I've started my engine with 65Ah removed from the 90Ah capacity without issue or even cranking significantly slower.

    While i did not monitor voltage as closely with previous batteries when starting, whether my stereo turned off during engine cranking was somewhat of a yardstick as to voltage held during this event.

    2 newish flooded marine 27 batteries in parallel did worse on this yardstick than my single Northstar AGM. I've never seen my stereo turn off during engine cranking with the Northstar. My stereo is wired to bypass ignition.

    For purely deep cycle duty I believe the Lifeline battery is unbeatable, but when dual purpose is required, perhaps Odyssey or Northstar are the better choice. Sacrifice some cycles for higher CCA/ instant available juice. How many cycles are sacrificed, vs how important those higher CCAs are,is certainly subjective with many many contributing variables, and I cannot guess.

    Not sure it is really worth stressing about though. I'll be deep cycling My Northstar-27 to death while doing my best to recharge it properly, regularly. So far, it is behaving well, and honestly, impressively so.

    The only noticeable difference in its current performance compared to when new, is the Super violently quick engine cranking ability is somewhat diminished, and it reaches absorption voltage with lesser amperages required than when new. But in terms of voltage held while discharging 45Ah from it overnight, it is like cycle number 20, while likely in the 365 to 400 deep cycle range and 32 months old.

    The 'Thin plate pure lead' AGMs might be just marketing mumbo jumbo to impress the neophyte, or perhaps they have found a good balance between instant power and cycling ability.

    I can only report on the performance of my Northstar as I use it, with more observation tools and interest in results than 99.9% of battery buyers, and So far, the Northstar battery impresses me.

    Would the Lifeline group 27 impress me as much in the same usage? I have no Idea.
  • Landy, your car has a gear reduction type starter motor. I really doubt if it draws in excess of 85 amperes during the summer.

    DAN, in 2 words "You can't" Only An Amp HOUR meter is capable of tracking long term variable discharge loads.

    Back to Landy: Yep you're right. Your battery will last a long time. But with .105" plates I can suck my Lifeline down to 5% capacity using my BiPAP and get away with it time after time after time. I am not easy on batteries.

    2,000 miles from here in Michoacan, my flooded cells are the same way. During a hurricane (we get those here as well) I draw those Rolls batteries down to 10% remaining capacity. Risking a pair of 100-meter dashes in a 130 kt wind is suicide for a person my age, so the generators stay in hibernation. Jesús, loses eight thousand dollars in Lobster defrosting, the Enramada goes belly-up and I just cannot bear the thought. By the way, a million dollar motorhome caught in a bad hurricane is going to leak water like a sieve. Quicksilver has no roof punctures and DuPont 5200 sealant around 5/16" thick tempered windows and it leaks.

    I have a Cruising Equipment Co. AMP HOUR METER I refer to. But during a hurricane it's C-Rations, 3-watt LED lighting, and a fantastic Endless Breeze fan set on "1" Four giant refrigerator-freezers suck up power. i could no more "guess" at remaining capacity than a Tibetan Monk could manhandle a diving rod.
  • Batteries are not my strong suit !!!. Another question, if I add up all my amps I'm drawing, how do I figure Ah to how long a battery will last? Dan
  • Hi, wa8yxm, are you talking "wet" or "AGM". Will check if I get Lifeline locally. Thanks for the replies. Dan
  • Both NOrthstar and ODyssey tout their pure Lead thin plate technology, and they have the super high CCA numbers which make them effective as dual purpose batteries. How many deep cycles they sacrifice for those higher CCA numbers is a question for sure.

    Lifelines CCA ratings are less as they are designed only for deep cycling, but surely have enough CCA for engine starting too. Lifeline also makes starting batteries.

    I'll be sure to let this forum know when my 0.060 thin plate pure Lead AGM battery fails in my deep/shallow cycling, and engine starting usage. At this point in its life is is retaining capacity to an impressive degree. So much so it is my only battery, for both house and engine starting duties and I've never had so much confidence in a battery I've owned. It will be 3 years old in November.

    If I wanted a pure Deep cycle AGM, lifeline hands down is the winner in my opinion.

    But I like seeing my voltmeter stay above 12 volts when cranking my engine.

    This single Northstar-27 at 930CCA,when new, could crank my engine faster than 2 flooded marine 27s at 1300CCA, in parallel could, and it also maintains higher voltage than them during 45AH of discharge.

    Batteries plus sells Northstar batteries as X2 power, and adds another year onto the 4 year free replacement warranty.

    On my experience with this battery I can recommend them, as long as one can high amp recharge them when cycled deeply. Without the high amp recharge, they will walk down quickly in apparent capacity. Sometimes it takes two back to back high amp recharges from 50% to restore performance.

    Since Lifeline and Northstar are about the same, price wise, if the higher CCA is not required for engine starting or high inverter loads, go for Lifeline. They are solid and dependable and pretty much the gold standard of deep cycle AGM.
  • MEXICOWANDERER wrote:
    For off-grid boondocking...

    I am impressed with the rapid recharging ability of top of the line absorbed glass mat batteries. Excessive generator run-time (wear-out and maintenance) fuel cost all costs cash. And at the end of a 5-year period, a "let's compare costs" between AGM and Flooded, may yield a surprise.

    Conversely I am not impressed with an AGM battery with .060" thick plates trying to compare itself with a Lifeline's .105" plates. Nor with the lesser battery's max charge acceptance of sixty some odd amperes versus one hundred plus for the Lifeline.

    My yearly fuel bill may exceed many forum participants. So does the prospect of a four thousand dollar Kubota "in-frame" rebuild job. This stuff makes me more sensitive to actual kWh production cost. There is no way in the world I or my kids going to have enough money to replace the bank of flooded 2-cell batteries. So I am looking at perhaps 10, 2-story 6-cell group 31 AGM Lifelines. Re-configuring the ferroresonant 6,200 watt charger, seeing what the 4024 Trace inverter "charge selection" options actually mean, and twisting down the regulator setting on the Lombardini 50DN Delco charging diesel.

    My question:

    Does Northstar publish the thickness of the positive plates on their battery? Will Northstar even answer an inquiry about this? Thicker (good quality) plates means a battery can take a lot more abuse and still come out with a smile - not something to be taken lightly.


    Think of it this way - an ordinary AGM versus a Lifeline can be compared (??) to judging a flooded car jar RV battery to a flooded Golf Car battery. It all depends on plate thickness and the integrity of the manufacturer. Rolls & Surrette and Concorde Lifeline both brag about the thickness of their positive plates. Other manufacturers are ashamed to admit their specs.

    Hmmmmmmm...
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Group 24 batteries are about 75 AH. a pair 150
    Group 27 is just under 100.. Pair just under 200
    Group 29 is just over 100, Pair just over 200

    GC-2-pairs.. These are six volt batteries so you must wire two of them in SERIES to make one big 12 volt battery .. or a 12 volt 4D, take your pick 220AH give or take 10 depending on the brand.

    And these are TRUE DEEP CYCLE not MDP which are really starting batteries so far far better for RV use.
  • I am impressed with my group27 Northstar, but it requires the occasional high amp recharge, after about 4 to 5 deep cycles, and 100% as often as possible.

    From 100% to 50% and about 350Deep cycles and many hundred more shallow cycles, the voltage it maintains under load for AH removed is nearly as good as when new.

    Northstar specs 14.46v absorption voltage at 77f

    use thick cables from the PD and it's 14.4v should be good enough.

    Exide batteries are not regarded well, from What i read online.

    Been a long time since I owned one.

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