Crazy Battery

[Spidey82]

My photon runs abt 3 hr and the light is really really dim.
i i use a multimeter to measure the voltage,
one is at 2.6v and th other one is 0.5v

wat on earth happen??
could it be that the 2.6v batt is spoit and it is the 0.5 one that powers the light??
the drop in light is rather sudden.
i thought it should last 12 hr???

 

[Elmie]

Exact same thing happens to mine...hmmm

 

[Badbeams3]

Was it run continuesly? (turned on and left on)

 

[**DONOTDELETE**]

Try it on the next set of batteries. I suppose a bad one (the 0.5V one). If you get the same result, one of the batts is shorted by something...

Bye,

 

[Chris M.]

My guess is you got unlucky and had a defective battery with a much reduced capacity. The weak one discharges faster than the strong one and it causes the light to dim fast. The stronger cell won`t get disacharged so much and so this will probably explain why one of yours is very low and one is quite high.

In some cases where many batteries are connected in series, a weak defective cell will discharge totally and then start getting reverse-charged from the current flowing from the other cells. In the very worst case this might cause it to leak but I`ve not ever known it to happen to me.

Any use?

 

[Badbeams3]

Well here`s my guess...you guy`s were trying to do a run time test to see how the Photon run time numbers would stack up against the Arclight...right...and based on that here`s my idea...small button type lights...pelican, photons and the like...are not made to run continuesly...the only heat sink is the batt...they are overdriven and there is quite a bit of heat transferd down the short lead and the batt overheats, the cemicals inside don`t like it and rebel by deciding to only last a short time to get even with you.

Ok guy`s, shoot me down.

 

[vcal]

yet one more example of why all new cells should be load tested B/4 using

 

[Badbeams3]

I really don`t think that would help Doug. Every time this has happened to my Photon I had ran it constant for some time. I think the little 2016`s don`t like being used as a heatsink for an extended period of time.

 

[vcal]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by KenB:
I really don`t think that would help Doug. Every time this has happened to my Photon I had ran it constant for some time. I think the little 2016`s don`t like being used as a heatsink for an extended period of time.<HR></BLOCKQUOTE>

Huh???

i.e. -how would that explain why one cell has so much less gusto than the other one?
(Spidey's perplexity)

 

[Badbeams3]

If you run a Photon with new batts constant the Nachia is overdriven and gets hot. The heat is transfered down the leads (one is real short in the Photon) and into the batts. The batts already are under a great load for there size and get warm on there own, but add to that the heat being transferd down the SHORT lead and into the batt...well the combination could shorten the life. It is also possible that more heat comes off one lead than the other(anyone know?) Not a problem if the batts have already been used to were the voltage is lower before running constant, but with new batts...left on constant...I think the heat inside the batt shortens the life of the batt...it`s just a GUESS but seems to fit the fact that (for me ) it always seems to happen when I have newer batts and run them for a long time constant...since I noticed this some time back I use another light if I need continuos light, and seem to have no more trouble of this sort from it.

 

[Size15's]

The point about reverse-charging is why you must never mix used and fresh batteries. Also, different battery types have different properties, and therefore mixing different types could also lead to reverse-charging...

I think the point about differential heat transfer and the batteries could be valid. It makes sense that batteries under different temperature conditions will have different properties. I don't know, but too much heat would damage the cell.

As to why heat damages the cell... Usually, heat helps reactions, but too much heat doesn't - it slows the reaction. High temperatures could physically damage the internal parts of the cell.

Al

 

[Badbeams3]

Brock, Craig, anyone...when overdriving a Nachia do both leads heat up the same (equally) or does one lead get hotter than the other?

 

[vcal]

My guess would be that the negative leg
would put out a little more heat, but I have never had this particular problem on my wht. Photon II though....(3 battery changes)
-esoteric people.., where are you??

 

[Badbeams3]

Try putting two new batts in and running it for a couple hours straight (or untill it starts to get dim). Then measure the voltage of each batt...I could very well be wrong and if so I would like to know...maybe it was just coincidence.

 

[vcal]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by KenB:
Try putting two new batts in and running it for a couple hours straight (or untill it starts to get dim). Then measure the voltage of each batt...I could very well be wrong and if so I would like to know...maybe it was just coincidence.<HR></BLOCKQUOTE>

'Ya know, Ken-now you've got my curiosity up-I think I'll do just that. (I've a load of 2016s around here)..

 

[Cyclops942]

Bang!

Did I get you?

Sorry, I couldn't resist.

 

[Spidey82]

i hardly use it for long.
normally tap it constantly to get ppl's attention. (for fun)

 

[Badbeams3]

In that case I would agree with the other posters, you probably just had one bad batt from the start

 

[Badbeams3]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by videocal:
'Ya know, Ken-now you've got my curiosity up-I think I'll do just that. (I've a load of 2016s around here)..

<HR></BLOCKQUOTE>
LOL, Yea, thats my problem too, the cost of them tends to stop me from running it to establish whats really going on for certain.

 

[Badbeams3]

Thanks, looks like my guess was wrong...probably just some bad batts then