Is this lead acid battarey servicable?
- Thread starter Rust_Belt_Pete
- Start date
The other thing you may want to consider is that the maintenance free battery has a valve to handle over pressure but aside from that it's sealed. That's the design. If you manage to get the cap off which most likely contains the valve you will (guess) ruin the sealed design point of the battery.
I’ve opened several “sealed” batteries and have not noticed any valves. I’m not saying there isn’t one, just I never saw one. The caps had orings and sealed fine after being opened.
Mine has it in the picture, left side lower 1/3rd little rectangular protrusion.
I don’t think it’s a valve, just an open channel for the gasses to escape. On the batteries I opened the caps were part of that large cover and it had that channel built in. I removed it as a whole unit. No valves were present if I recall correctly.
Well if there is no valve then it's not a maintenance free battery.
By definition a maintenance free battery is either SLA (battery for commercial alarm systems) or VRLA.
The only way a normal battery with liquid battery acid can be maintenance free is if it was a valve to to hold in the gases, getting them to recombine into water and back into the liquid battery acid. Is is completely sealed like a SLA.
I remember peeling off the maintenance free sticker that was on top, so I’m pretty sure it was a sealed battery.
As far as the valve goes, I never paid attention to it, so it could’ve been there.
Regardless, your assertion that these do not need to be topped off is simply incorrect. The electrolyte level on these can definitely go down despite the seals and valves. And one can extend their service life by checking the level and topping off with distilled water if needed.
With all the talk of servicing batteries I decided to check the caps on my 1 year old Everstart Max. Sure enough all 6 cells needed some water, but none were below the lead plates. The battery had two square removable caps. This battery was a 36R and few numbers down the line did not and were instead maintenance free. I put it on a smart charger to charge it up fresh after the distilled water was added. All good with 12.7 V and 812 CCA after driving it for a while . Thanks for the reminder.
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But that is not the design point. If the battery was properly manufactured, and no one has messed with the caps and the cells did not get over pressure from overcharging then there is simply no way for the cell to loose water. It's sealed. But from your experience it can happen.
No argument there. The design is sound and it does work because battery maintenance is a thing of the past and only a small minority like me still check the electrolyte level from time to time, where before it needed to be done quite often.
twouvakind
Site Donor 2025
Plenty of battery "openings" on YT.
You are in Texas right? Hot there for batteries. Maybe valves have vented. When you added water were all cells down roughly same amount?
From East Penn
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A charging voltage over 14.6 volts will cause the valve to open.
Once the valve opens it will release hydrogen gas. The battery is not ruined because the valve opens. Yes, the heat can cause overcharging.
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A charging voltage over 14.6 volts will cause the valve to open.
Once the valve opens it will release hydrogen gas. The battery is not ruined because the valve opens. Yes, the heat can cause overcharging.
Agreed. But you don't really know if it has happened. I suppose if your alternator went haywire and was overcharging you can assume it.
But like many things, only card carrying BITOG members would check a maintenance free battery. I doubt a mechanic at a shop would. Chance of damaging the valve or seal. Charge the battery and if it does not pass a battery test, replace it.
I for one am moving to AGM. Of the 6 batteries I have, 3 are AGM. The $200 ones not the $400 high end ones.
In my experience it’s usually one or two cells that are low. And it’s the ones close to the terminals, not the ones in the middle.
Those cells would have more surface area to absorb heat.
From East Penn when I asked about caps on maintenance free batteries.
Do not remove caps. Do no try to open caps.
Do not remove caps. Do no try to open caps.
I would not expect any different answer from them. These days nobody wants you to do anything, just throw away and buy more stuff. It’s for your own good and safety
There are many forums that discuss member’s personal experience with longevity of their car batteries but very few mention if they are using a maintenance free battery or a conventional one with opening caps. I recently purchased one of each. It seems luck of the draw to even have a choice for the battery model you require.
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