Batteries - What's worth it, what isn't??

Now there's a really useful comment that shows the breadth and depth of your boating acumen. I understand they wrote a song about it, called "Zip -A-Dee-Doo-Dah!!

Thank you so much!!

I could write a book on how to ruin batteries. Unfortunately I don't have time to write it right now.

Also unfortunately it may take a book to give you the answers you're looking for. Here's some basics: Yamaha should have a spec for the battery the engine requires. After that consider electrical loads. If your current battery has served well replace with the same amp-hour rating or higher. AGM is good, but probably not necessary. To really get maximum life (and the benefit of the price) you usually have to have a charger that can be set for AGMs. Starting vs. Deep cycle is a game of plate thickness. Thinner plates charge and discharge faster so good for a short burst like cranking, less so for long term drain like house loads. Again, look at your current AH rating and defer to that. I think the whole "Dual purpose" thing is more marketing to people who can't decide than anything else.

AFAIK, there are only three actual manufacturers of batteries. East Penn (Deka), Exide and Johnson Controls. Everybody else is rebranding one of them. Unfortunately they will all make batteries to whatever price point the rebrander wants. You can try to get the seller's MSDS for a battery and it will probably tell you who makes it. i.e. NAPA brand batteries I had in my boat when I got it were made by Exide. Generally I try to stick with Dekas and avoid the discount and Costco batteries. OTOH, if you don't mind swapping a battery once in a while those lifetime warrantys are hard to ignore. Also, those $5 Harbor Fright maintainers are a godsend for applications like boats that suffer from intermittent use. That has been one of my best battery investments ever.

Don't know if that helped or made it worse, but there you go.

Thanks for the response. I'm glad that really experienced folks like you can tend to chase their tails on this topic. I've been doing this for a week now, LOL. From what I've read the "DP" batteries have plates with thickness between the thinner cranking ones and the thicker deep cycle ones.

Point of info, but I just heard that Crown bought out Exide. Current battery is an Exide AGM and I'd love to replace it, but cannot for the life of me find one.

I think Avenger makes a lot of good points, and he's right about the limited number of sources for commercial car/boat batteries - at the end of the day, 99% of them come from the same 3 vendors. Based on the research I did, the deep cycle vs. cranking debate was only relevant if you were going to push the battery to completely discharge on a regular basis.

In your case, I think you might be overthinking it. A battery from Costco will suit you just fine and come with a 3 or 4 year warranty. It'll be below a hundred bucks (I bought two group 27's last year, pretty sure they were $90 each), and when the voltage falls below 12V after charging they'll replace it for you no questions asked. I would say you're better off spending the extra money on a dedicated marine charger (if you don't already have one) than going for a more expensive AGM battery. Might also want to invest in a jump pack since you've only got one battery, they're lightweight but the amount of power a starter needs in good weather isn't that high, could save you a call to Sea Tow at some point (or at least give you enough juice to power your radio while you wait for them).

I think Avenger makes a lot of good points, and he's right about the limited number of sources for commercial car/boat batteries - at the end of the day, 99% of them come from the same 3 vendors. Based on the research I did, the deep cycle vs. cranking debate was only relevant if you were going to push the battery to completely discharge on a regular basis.

In your case, I think you might be overthinking it. A battery from Costco will suit you just fine and come with a 3 or 4 year warranty. It'll be below a hundred bucks (I bought two group 27's last year, pretty sure they were $90 each), and when the voltage falls below 12V after charging they'll replace it for you no questions asked. I would say you're better off spending the extra money on a dedicated marine charger (if you don't already have one) than going for a more expensive AGM battery. Might also want to invest in a jump pack since you've only got one battery, they're lightweight but the amount of power a starter needs in good weather isn't that high, could save you a call to Sea Tow at some point (or at least give you enough juice to power your radio while you wait for them).

Yeah, I'm really overthinking this one to the point of being ridiculous, especially since I always carry a 1000 amp jumper pack. If it wasn't a single battery rig, I wouldn't have even given a second thought of my previous MO of using inexpensive batteries.

Yeah, I'm really overthinking this one to the point of being ridiculous .......

It's ok ........ its been a long winter. 🙂

I use two truck batteries in my mako,same ones I use in my dump truck there Excide 950 cca,get them at Gabriel Mack about 86 bucks apiece..

As Avenger mentioned, there are only three manufacturers of automotive and I assume marine batteries. Johnson Controls, Exide and Interstate.


Most of my experience comes from car batteries. Currently in my boat I have the Optima Blue Top Marine Battery. Not sure I recommend that. When fully discharged they may not recover well.

I have an Interstate in one car that lasted 10 years. I have also found that Legend batteries are pretty good. Discharge them and they do take a recharge well.

I also try to maintain them. My battery is out of my boat and I have recharged it and put it through a refresh cycle (on the recharger) 3 times during the winter. Letting just sit seems to shorten the life

I had an Interstate battery in a van for 9 years. When i got a new van and junked the old one I kept the 9 year old Interstate battery as a back up in the new van( before the days of battery booster packs). It held the charge for another 4 years. I worked for an auto collision group and we only used Interstate batteries as replacements. same as our fleet customers.

I thought it was a "fluke" that my battery lasted 10 years. If the OP is interested Interstate makes marine batteries:

I had an Interstate in my Maxima, I knew it was time to replace it before the winter. Turns out it had a NASCAR decal on it, which they stopped putting on their batteries 12 years earlier.

I love my Everstarts ........

I love Interstate for my truck and cars as well. I also have a single battery boat, and I believe that battery will be entering its fourth or maybe fifth year. Last year I picked up one of those lithium "booster" packs to replace that 20 lb monster the size of a small shredder. Sure, they warn about getting it wet but I don't intend to take it out of its little container (it fits in a .30 cal ammo box) until its needed. https://www.amazon.com/dp/B073VZ9H7Q/ref=psdc_318336011_t3_B07JM5V8BX
Each time my boat battery has failed, it did so in my driveway or at the ramp. No problem, I live two blocks from the town ramp and just dump the boat in my driveway and grab a kayak.
For the last ten or 15 years I avoid buying anything from Sears like the plague. Their die hard batteries were horrible.

I've had an Interstate in my Grand Cherokee for going on 10 years now - still cranks on the first twist of the key

I've had an Interstate in my Grand Cherokee for going on 10 years now - still cranks on the first twist of the key

If it ever got to zero degrees in Onancock it might not..

If it ever got to zero degrees in Onancock it might not..

it's gotten close a couple of times - 8, 10 degrees.....................

It was probably 5 years old when I left NY

Yeah, I'm really overthinking this one to the point of being ridiculous, especially since I always carry a 1000 amp jumper pack. If it wasn't a single battery rig, I wouldn't have even given a second thought of my previous MO of using inexpensive batteries.

We've all been there.