MightyMax 200AH agm battery

[vientoman]

Has anyone had any experience with a MightyMax agm 200AH 4D battery that is sold by Walmart for sailboat use. I realize that an AGM battery for half the price is suspicious but I am nonetheless interested in the possibility. From the limited specs it is difficult to ascertain whether or not such battery is suitable for cyclic use.

source: https://www.walmart.com/search/?quer...20battery%204d

[Scott Berg]

If these are the Mighty Max batteries made in NY it might be interesting; check out https://www.mightymaxbattery.com/p34...-200-amps.html

[john61ct]

Nope nope nope.

Nothing in 12V Starter form factor sold in big box retail is true deep cycle.

Biggest giveaway is any mention of use as a starter, any CCA specs.

Doesn't mean it couldn't be made to last "long enough" if well cared for, but say 50% cycling I'd be surprised over 500 cycles.

I'd love to be proven wrong though. . .

[vientoman]

[QUOTE=john61ct;2347297]Nope nope nope.

Nothing in 12V Starter form factor sold in big box retail is true deep cycle.

Biggest giveaway is any mention of use as a starter, any CCA specs.

Doesn't mean it couldn't be made to last "long enough" if well cared for, but say 50% cycling I'd be surprised over 500 cycles.

I'd love to be proven wrong though. . .[/QUOTE


I don't know of too many lead acid batts that can handle %50 discharge and 500 cycles.

[vientoman]

they claim:


The state-of-the-art, heavy-duty calcium-alloy grid provides the ML4D with exceptional power, performance and service life. The thicker plates of the ML4D allows you to discharge deeper than other batteries,

[john61ct]

Originally Posted by vientoman

they claim:

The state-of-the-art, heavy-duty calcium-alloy grid provides the ML4D with exceptional power, performance and service life. The thicker plates of the ML4D allows you to discharge deeper than other batteries,

Yes, those "other batteries" are plain cheap starters, as opposed to true deep cycle ones.

Originally Posted by vientoman

I don't know of too many lead acid batts that can handle %50 discharge and 500 cycles.

That would be an absolute minimum AFAIC to qualify for the term, for example the cheapest GC2s from Sam's Club and even Costco, excellent value for money, especially the former.

Hundreds of models do better than that if not abused.

You just don't find them marketed as automotive or so-called "marine" through Big Box, in 12V starter sizes.

Rolls/Surette, Odyssey, Northstar, Lifeline, Firefly, Trojan, Superior, U.S. Battery, Crown, ​Deka/East Penn, all have excellent quality lines that can perform better after years of hard service than the big box "heavy duty" will off the shelf.

Spending more up front will definitely save you money long term, IF you know how to care for them. If not, like many people going to murder a new set every year or two, just save your money and get the Duracell (actually Deka/East Penn) GC2 at Sam's Club or Batteries Plus, can't get decent quality true deep-cycles any cheaper than that.

[john61ct]

PS AGM and Gel are also lead-acid, not necessarily longer lasting, in fact more susceptible to abusive conditions.

[robbievardon]

I am going to replace house batteries shortly and by chance passed the battery dept in Canadian Tire. My on boat requirements are pretty minimal at the moment day/weekend sailing with no major appliances on board,shore power at slip and 12 volt charger.Anyone know anything about CT*s batteries. I fully understand you get what you pay for but it is a (probably) one season job?

[dmalcol1]

Both Walmart and Canadian Tire have good costumer service departments. A live-aboard friend of mine returns his batteries every couple of years employees in service department just smile now he is a regular. From that point of view Walmart and Canadian Tire batteries could be great value/dollars. It all depends on your requirement of product, great service department does you no good if you are thousands of miles away.