What is the green light on the Fullbat U1-9 lawn mower battery?

[Christophe]

I just changed the battery of my stiga park, I found a Fullbat U1-9 24Ah.

It has a green light whose meaning I don't know...nothing at all about it in the instructions attached to the battery...

At first I thought it was a little voltage indicator LED but actually no, it doesn't glow at night...So I'm assuming it's a chemical indicator that indicates the quality of the electrolyte?

Anyone know this stuff?

fullmat.jpg (370.2 KiB) Viewed 3501 times

fullmat green light.jpg (344.71 KiB) Viewed 3501 times

[Macro]

Yes it's a float that sinks when the density of the electrolyte drops (and the battery is discharged or lacks water) It's not much use we see plenty with the green light which are good for the crusher. ..

[Christophe]

Ah not bad that (if it was reliable)... But uh... how do they make the thing flow in case of discharge?

I didn't know that the density of the electrolyte varied during discharges...

[Macro]

Ah not bad that (if it was reliable)... But uh... how do they make the thing flow in case of discharge?

A boat floats on salt water and in fresh water... It can sink... Well the green float, on discharged electrolyte... It sinks....

We are roughly the same age, Christophe... I remember an experiment in physics and chemistry where we weighed the electrolyte of charged and discharged batteries...

Battery charged, the electrolyte has a density of 1,28 kg/litre. During discharge, it becomes depleted in ions and its density decreases to approximately 1,10 kg/

[Christophe]

Well then!

You're going to take me for a fool (which would certainly please some here...) but I knew that on lead batteries the density of the electrolyte varied according to its age and degradation but not on the level of charge! Never did this experiment in chemistry class...

In short, the level had already started to collapse, you have to believe...

[GuyGadeboisTheBack]

[Christophe]

Thanks Guy! I saw I understood!

Well, why don't we put this systematically on all lead batteries all of a sudden?

[GuyGadeboisTheBack]

Maybe because it was an unreliable gadget? I had a battery with the green light, but it was dead...

[Christophe]

Yeah that's what Macro said above...

Still, I've seen dozens of lead batteries in my life and this is the first time I've seen this gadget...

ps: the old stiga battery is dead too and the optimize says it's good...

[sicetaitsimple]

but I knew that on lead batteries the density of the electrolyte varied according to its age and degradation but not on the level of charge! Never did this experiment in chemistry class...

Hey, the "young people"! Lead batteries for "domestic" use have been "sealed" for a long time, there is nothing more to do.
But "in my time", they were not and it was necessary to regularly add distilled water by opening the caps of each element. We generally took the opportunity to check the state of charge via an "acid weigher". I must still have one somewhere, but it's definitely been over 30 years since I used it!