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Battery (Sealed vs. Unsealed)


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Opinions welcome on the merit of a sealed battery vs. the kind with the caps.

Even the sealed batteries have a little hose, possibly to allow for gas expansion and release, so as to prevent KABOOM.

This outlet would seemingly allow for a gradual loss of fluid by evaporation, albeit small.

It seems that the type of battery where you can add distilled water and even recharge the acid if needed makes more sense or is this an attitude left over from my days on the Old Gen USMB, where everything was expected to last forever??

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I would go with the traditional flooded cell battery which is the kind where you add water...as long as you remember to check and add water once in a while. They are cheap and if maintained can last 7 to 8 years (usually less, though). Also keep the battery clean to minimize self discharge.

 

If you get a gel cell or AGM (absorbed glass mat) then you can't add anymore electrolyte if you loose any. But they are better batteries in that they recharge quicker (higher acceptance rate) and lower self discharge. But they are more expensive. If you have extra cash go for an Optima but there is no guarantee that it will last any longer than a flooded cell...but it will cost you a lot more.

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The sealed "maintenance free" batteries are just ordinary batteries with maybe a little extra fluid capacity and grid matrices that are made of calcium instead of antimony (unless they changed this in the last decade or so). The calcium matrices tend to cause less electolysis of the water than does the antimony, but is FAR more fragile; it tends to crumble after discharging, which is why it is often said that each full discharge reduces m/f batteries capacity by 1/2.

 

Traditional batteries tend to have thicker, more sturdy grid plates, and you can replenish the water and check the electrolytes SG, but the tradeoff is that they pack less current producing capacity into the same form factor and require you to check the water once in a while.

 

The "maintenance free" batteries pack more capacity, and fit into the concept of "just weld the hood shut" that the gov would really like to implement. But they are fragile and don't tolerate deep discharge.

 

And then there are the cool "Optima" batteries...

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"just weld the hood shut" LOL

The sealed "maintenance free" batteries are just ordinary batteries with maybe a little extra fluid capacity and grid matrices that are made of calcium instead of antimony (unless they changed this in the last decade or so). The calcium matrices tend to cause less electolysis of the water than does the antimony, but is FAR more fragile; it tends to crumble after discharging, which is why it is often said that each full discharge reduces m/f batteries capacity by 1/2.

 

Traditional batteries tend to have thicker, more sturdy grid plates, and you can replenish the water and check the electrolytes SG, but the tradeoff is that they pack less current producing capacity into the same form factor and require you to check the water once in a while.

 

The "maintenance free" batteries pack more capacity, and fit into the concept of "just weld the hood shut" that the gov would really like to implement. But they are fragile and don't tolerate deep discharge.

 

And then there are the cool "Optima" batteries...

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I've had a maint. free ACDelco for over four years now. I like it because it does not corrode the posts and cable clamps. It does have two vent holes, but those are used if a relief valve opens which is not designed to be a regular occurrence.

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the sticker and they have filler holes. I can buy two Interstates for one Optima, so even though they are cooler I have Interstates in my cars. I change them every three to four years and never give them a thought. This has worked for me for the last 15 years or so.

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I have used Varta maintenance free. They don't seem "fragile", and there is no discernable drop in cold morning current - based on starting.

 

Optima is made by Banner BAtteries, and I had a bad experienc with their maint free batts. The posts are too small a diameter, my earth couldn't get a tight fit. So I returned it.

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