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MK replacement house battery

Has any one found a good place to purchase MK replacement batteries?
Or would the Lifeline series be a suitable replacement?

We currently have 3 MK's for house batteries.

Dick & Sue
'99 U320, 36'
2015 F150 4x4 Supercrew
M & G with brakeaway system
Blue Ox Avail 10,000# tow bar
Grosse Ile, Mi.

Re: MK replacement house battery

Reply #1
8G8D | MK Battery 12v 225 AH Deep Cycle Gel 8G8D Battery
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan

Re: MK replacement house battery

Reply #2

Or would the Lifeline series be a suitable replacement?

Lifelines would certainly be a suitable replacement.

Decisions, decisions.
Jan & Richard Witt
1999 U-320  36ft WTFE
Build Number: 5478 Motorcade: 16599
2008 Roadtrek Adventurous RS Sprinter
2011 Jeep Wrangler Unlimited
Jan: NO5U, Richard:KA5RIW
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Re: MK replacement house battery

Reply #3
The price for batteries these days would mean that you almost have to take out a loan for. them!! We have to add 30per cent to those prices. Ours are 7yrs old but seem to be doing well.
JohnH
Coachless, now use aircraft.
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: MK replacement house battery

Reply #4
No source but the choice between  MK gels versus Lifeline AGM's is influenced by several factors.

If you plan on adding significant solar panels then the amount of charging amps that the possible panel system can put out can help determine your final choice along with a capacity difference.

The mk gels different chemistry internally does not sulphate.  Can be slow charged without damage. 

Lifeline AGM's I think were designed for either a 1/5th C  charging rate or a 1/20th C extremely slow charge.

Actually both batteries were made to be charged similarly as far as I know.

If the Lifelines start to lose capacity from lower than its design charging rate they can be equalized to attempt to restore capacity.

Your inverter if it's still the oem Heart freedom 25 mat not have a lifeline correct setting in its battery type as the Lifelines require .2 less volts while charging as they have much larger internal connections and charge 20% faster because of that feature.

They are also 250 amp hours versus the mk gels 225 or a bit more after 15 cycles of use.

BOTH batteriy types REQUIRE a battery temp monitoring system. 

My 97's non sine wave freedom's serial number was before 100,000. Could not take the battery temp controls input.

Yours can and should be installed on the batteries.  Much longer battery life if the charging voltage is correct for the battery temps.  Without it you are only correct at 77 degrees.  Above that temp you are overcharging the batteries.  Below that you are undercharging them. 

The MK gels do not need equalization ever.  Different chemistry.  Every unicoach made came with mk gels.

The 20 years plus time that has passed has brought major improvements to the charging and inverting systems.

Latest inverters like a magnum from Sensata Tech have a built in profile for the Lifelines.  Not all have that.

Plus the battery temp,input that you could add to,your Freedom.

I called the mk engineer when i was replacing my non mk gel house batteries and he mentioned that East Penn had made several design changes that should make their batteries have a greatly extended life beyond the previous 10-12 years or 2,000 50% discharge cycles.

Normal AGM's are one half the cycle life and if not charged correctly are are not equalizeable.  Once capacity is lost it's gone forever.

I can send you both manufacturers tech sheets if you want as I think I have pdf's of both.

I have been slowly upgrading our charging system for a possible future refer change and a solar upgrade as time goes by.

The magnum now offers a power trace solar controller that can be a stand alone unit with up to 100 amps of solar input per stackable unit.

Plus they offer a Battery Managemt System with a shunt in the negative cable that allows both the inverter/charger and/or the solar controller to both use the battery temp and battery management system to both adjust the charge rate from either the solar through the power trace and/or the inverter and learn the batteries actual ability to take a charge and discharge.

My guru buddy is adjusting the charging profile in his Magnum installations using the Magnum ME-ARC controller to alter the normal switching out of absorption at 2 hours in the ME-RC non advanced remote.

In other words the MK batteries have been improved and major changes have occurred with the inverter/chargers systems themselves.

Most here noticed a lower charge rate from our Heart Freedoms chargers.  Turns out the internal contactors inside the hearts corrode from wear and use and cannot put through the original current they were designed to output.

If you want the rest of the Magnum integrated systems info please let me know,

The newer inverter allowed an fully integrated complete system made in the USA system with available parts and service that has much higher capacities and adjustments.

Auto gen start, advanced controllers, a battery management system that learns the actual batteries condition and battery temp monitoring input that your freedom can have and full sine wave better power and fully integrated solar controller with up to 100 amps of 240 volts capacity.

The MK's and the temp monitoring of the batteries would be a strong choice and if it would help you the rest can be added as possible.

We also changed to an auto combiner for the battery banks.  Greatest thing since sliced bread.  For sure the engine batteries get charged and are never damaged from being discharged by accident.

My small solars panels output is enough to activate the combiner automatically.

The motorhome IS the 12 volt system and the life blood of the coach.

The almost amazing technological advances now available make the coach much more useable IMO.

I am future planning I may add two more mk gels if I add a residential refer in the future, 

 All the electronics first. Then more solar then the additional batteries if needed.

Lastly the refer.

My two cents. For sure others will have input here





"Riding and rejoicing"
Bob & Susan
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: MK replacement house battery

Reply #5
Are you wanting AGM or Gel ? I bought my AGMS from O'rilleys auto parts around 400$ ea 4 years ago. We boondock most of the year and they are still going strong. Lifelines age great as well just pricey. If you go with O'rilleys be sure to tell them you want all of the batteries to be the same recent date code, no more  than 3 or 4 mos old. Most store don't sell a lot of them they will most likely have to order them.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: MK replacement house battery

Reply #6
Lots of options here.

The MK batteries are rated at 225 amp hrs, 675 amp hrs total, for about $2340.  $3.47 per amp hr.
FullRiver 12v 8Ds are rated at 260 amp hrs, 780 amp hrs total, for about $2100.  $2.69 per amp hr.
LifeLine 12v 8Ds are rated at 255 amp hrs, 765 amp hrs total, for about $2100.  $2.74 per amp hr.
FullRiver L16 6v batteries are rated at 430 amp hrs per pair, 860 amp hrs total, 4 for $2560.  2.97 per amp hr.

Fullriver Battery DC260-12 Product Information
Fullriver Battery DC400-6 Product Information

4 Fullriver batteries will fit in the floor in a single level where you 8Ds are now and without the upper rack will weight about the same.

You may get more total cycles out of gel batteries than AMG but they have less capacity.  Lots of arguments and opinions here.

Picture shows 4 DC400-y where my LP tank was.  And a simple rack for 4 batteries.


Re: MK replacement house battery

Reply #7
I purchased my batteries at oriellys also and they have me a military discount. Around $800.00 for two as Bruce stated.
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: MK replacement house battery

Reply #8
Mk gels are the least expensive batteries from them per cycle.  The MK engineer thought that the pre charged plate upgrade in the batteries plate production which catches out of spec plates before installation and a upgraded plate mounting and separator updates may double their already 10-12 year nominal proven long term lives.

IF and when you become sensitive to the actual batteries capacity where the resting volts versus the amp hours used no longer match versus when tested after 15 cycles on non lifeline AGM's as the batteries age from use and/or non correct charging rates and temp controlled charging it's non fixable other than Lifelines and if you have a inverter/charger that has the specific charging profile for the Lifeline AGM's. 

Made in USA by Americans on top of it.

US military uses Lifelines.  With a perfect updated charging system and a large solar system I might consider the Lifelines myself.


But other than alternator and/or the magnums charger I do not know of a motorhome roof sized solar system capable of charging a three or more battery bank at the correct for long life 1/5th C charging rate.

At that point the factory and my guru both only install the mk gels as they cannot be damaged from the lower than 1/5th C charging rate.

My power trace solar controllers can put our 100 amps each  IF if your solar can output that much which would be closer to the alternators 160 and the Hearts 120 which is close to the magnums output.

If I was to engineer a solar system with 22% efficiency panels it may be possible to exceed the 100 amps rating.

At that point a second power trace can be stacked so up to 200 Amps would be possible.

At that point the ability to correctly charge the Lifelines off of a optimum solar system might sway me to use them.

20% faster charge input versus other AGM's and gels might help with less gen run time or less input from solar,

Without the trick system the easiest, longest life is the mk gels and a battery temp monitor  system which is required  by both battery systems manufacturers you wish us to compare.  As you did not ask about other brands I will respect your wants.

There was a reason every unicoach made had a matching charging system both from the alternator and the inverter/charger and came with mk(east penn) gels. 

Less phone calls.  Happier customers. Bette trade in/resale value to knowledgeable customers or dealers.

If i was taking a Foretravel unicoach in trade without oem batteries on both the engine and house I would and have deducted the full price of new batteries from the appraisal.

Every prospective owner who has had an rv before asks lots of questions about the exact details of the charging system and the batteries and their tested or verified condition.  Wouldn't you? 

I found out long ago that not updating the electronics and new high quality batteries cost me double or more in the selling price and made a knowledgeable customer doubt the rest of the coaches condition and price.

Almost all old rvs had battery issues.  Hence a lot of questions about every detail.

I have seen customers relax during a  walk around when you can positively demonstrate the electrical systems proper  condition and design. 

Plus I would show the marine fire resistant UL battery cabling for their safety. 



"Riding and rejoicing"
Bob & Susan
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: MK replacement house battery

Reply #9
I am a little surprised that others have not informed you, Dick & Sue that MK is just a brand label of East Penn Battery, who make identical batteries under their MK, East Penn, Deka labels.

And East Penn also makes the identical battery for many national chain auto parts stores with the chain's label stuck on the side of the battery. And batteries at national auto parts stores have a retail price that is very often discounted by $200-$300 if you 'bargain/ask', sometimes better done by phone.

In 2008 we replaced our MK 8G8D batteries at a CarQuest store for $450 each, who had to bring them in from the local East Penn warehouse. In their desire for a quick delivery, the CarQuest label was not put on and the battery came with a Deka label. In 2012 we decide to buy new 8G8D batteries at NAPA for $600 each, and those also came with Deka label.

All these batteries are identical in every way, except for side labels, same gray color, same rope handles & post and same exact outer dimensions, shape and look.

A similar size, shape & color East Penn battery is made with AGM technology and called 8A8D.

Also be aware both 8G8D & 8A8D come in two post styles, common, familiar 'automotive (tapered) posts' and forged terminal for bolt attachment.

Re: MK replacement house battery

Reply #10
Research your options.  In 2013 I decided to replace my OEM gel house batteries with gel 8D's.  I contacted Battery Giant in Cincinnati after seeing that they offered private label 8G8D batteries.  After talking with the manager and doing my own research I found these are the same 8G8D batteries made by DEKA/East Penn under private label.  I negotiated a price of $500 each with them installing them for free.  I am still using those 2 8G8D batteries today- 5.5 years later.  I expect to get 10 years or more out of them .  Research, negotiate, and see what you can do.

Best of luck                                ^.^d
Ted & Karen
2001 U270 36' - sold after 12 years full timing

Re: MK replacement house battery

Reply #11
I fully expect that private label, Deka and others are the same battery.  But I cannot prove it. Neither can anyone else.

I found that the more optically perfect windshields from Fords suppliers went into the production line cars and trucks.

Less than perfect went into the parts department.

All brands.

All are tested.  No one really knows.  Probably exactly the same.  Probably.

Lifeline sells no private label that I know of.

The east penn steps and technology in production  are amazing. 

I will post it.

http://www.eastpenn-deka.com/assets/base/0139.pdf

Here is the lifeline one

http://2cw8eb1vmmgg3g5i7jzt6upo.wpengine.netdna-cdn.com/wp-content/uploads/2015/12/6-0101-Rev-E-Lifeline-Technical-Manual.pdf
"Riding and rejoicing"
Bob & Susan
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4