Diehard Battery with 7 cells

[philc]

I am wondering why there are 6 cells on my battery, all in row as usual but there is an "extra" cap offset from the row of 6 just about at the mid section of the battery making what appears to be a 7 cell battery.
Its old and came with the bike so I dont know its history.
Is it a cell that requires distilled water like all the rest or is it an overflow of some sort?
Thanks for any help
Phil

 

[wilcoy02]

I have also wondered what that cell is for.

 

[dan filipi]

I hate to guess but I think that would be a vent.
I searched some for a picture of that battery top but came up empty.
Can you post a picture?

 

[mwbill37841]

:headscratch: i may sound dumb but maybe someone could get a hold of a battery manufacture and ask them that question. i think they wouldn't mind telling us. :grin:

 

[DaveO430]

I am pretty sure Yuasa manufactures all those batteries (no matter who's name is on it) with the 7th cap. No idea what it's for though.

 

[AApple]

It's a metric battery.... :smilie_happy: :smilie_happy:
I gots a buddy that werks for a battery manufacturer..if I can find a good pic of one like that, I'll see what he says. :read:

 

[wilcoy02]

here are three pics

 

[cooltech]

my battery has is the same 7th cap must be just a vent

 

[philc]

Ooops, I put water in there!?
It is old so if I have to replace it I wont be too bummed out

 

[philc]

Oh I think I get it now, an overflow valve sorta.
Thanks.

 

[mike in idaho]

Some bikes use a battery sensor, that extra hole is where it goes.

 

[joedrum]

:smilie_happy: :smilie_happy: :smilie_happy: oh my mike ....they do ...sheeesh .... :smilie_happy: this is to good :smilie_happy: im taking the fifth again :heat: you you think the answer would have came before now :hihihi:

 

[wilcoy02]

that makes sense. battery sensor.

 

[David Mantle]

Extra hole is for the insertion of a battery condition sensor . I use a Bosch made battery and it does not have this 7th cap.

With a fully charged battery and correct specific gravity each cell should show no more than 2.2 volts . This gives a total reading of 13.2 volts for a fully charged battery. Hence the charging from the generator , via the reg/rectifier , should read approximately 13.5 . This allows for a constant slight charge to maintain battery condition. Most bikes show a figure of between 13.5 and 14.5 when in normal use with lights on.

Just a thought - hope it helps.