Is it possible to bypass a cell on a 3 cells 6 volts lead acid batteries ?

[paulcheung]

Hi guys,

I have 3 Rolls S460 lead acid 6 volts batteries are give problems. one cell on each of these batteries are dying. I wonder if is possible to by pass the dying cell to make the battery 4 volts then I can connect the 3 batteries series to get back a 12 volts system. the inter connect bar of each cell is not shown. the dying cells are the end side of each battery. If I can find the inter connect bar and connect a connector to it so I can use it to connect to other battery instead the original battery post on the dead cell.

Thank you.

[Mike90250]

If the cell is dead, than the battery is toast, so digging into the case is only going to void the warranty.

You will be exposing the acid, with all the fun involved

[jflorey2]

I have 3 Rolls S460 lead acid 6 volts batteries are give problems. one cell on each of these batteries are dying. I wonder if is possible to by pass the dying cell to make the battery 4 volts then I can connect the 3 batteries series to get back a 12 volts system. the inter connect bar of each cell is not shown. the dying cells are the end side of each battery.

There is no practical way to do that.

[paulcheung]

If the cell is dead, than the battery is toast, so digging into the case is only going to void the warranty.

You will be exposing the acid, with all the fun involved

Rolls already told me they only be able to deal with ONE battery pro-rated and the others are on my own. So warranty is no longer an issue. Any members on this forum has open any Rolls S460 or similar batteries? is the internal connection right under the cover? high above the acid? I am thinking may be I drain the acid in that cell and cut open a hole on the top and make the connection. will that work?

[Mike90250]

You are going to want to solder a lug to the internal connection bar, can't do that in a tiny hole. And you need a big hot way to solder in 5 seconds, to not heat up the bar and melt the case. A local battery shop has the tools to re-cast a terminal, maybe they can open the case and cast a terminal onto the interconnect

[Raul]

I would do it. Once you take all the safety precautions involved working with/ near acid I would proceed with the following:
-extract acid out the dead cell
-drill with a hole saw on top cover on the dead cell, right above where the interconect crosses from middle to the side. That is next to the side post of dead cell .
-once I exposed the bar I cut it with a hacksaw to eliminate continuity to the dead cell, but leave a good flat stub to work with.
- drill the stub, then tap with a self drilling/ tapping screw/ bolt to create a connection for a lug.
The top cover is heat welded and brittle , no need to take it of to expose the 2 healthy cells.
Just drill above the dead one.
The interconects are stagered from outside post to the middle, hence the posts are at opposite sides.
Hope you andestand what I mean.

[Sunking]

Hey Paul hope things are OK, sounds like you have issues.

Seriously if you have a bad cell = bad battery. No way to repair it. You need replacements.

[paulcheung]

I am good. thanks Dereck. I am not looking to restore(repair) the batteries to make new again. just that these 3 batteries have 6 fairly good cell in them and I have a small 12 volt system that power 2 small pond pumps. instead buying new batteries for this small system. if I can drill 3 holes and connect the 6 good cell together I can use it. it might last a while.