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Why a Dead Alkaline Battery Bounces [video]

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Re: Why a Dead Alkaline Battery Bounces [video]

#11

Post by mhandley »

haar wrote: post #7

I think one of the bits I liked most was "Romeo (Retired Old Men Eating Out) Club" - looking at its website it seems like quite a large thing over there. I know that my Grandma goes to something similar (restricted to just tea and bingo), but it makes me wonder if a similar organisation exists in the UK; a lot of the older folk I know just aren't very social any more, simply due to the fact that their social groups h…

One excellent organization is U3A http://www.u3a.org.uk/ My father runs one of their groups that specializes in studying geology, and they regularly have a hundred people turn up to the seminars they run. Science and social go well together when you've lots of free time.

Re: Why a Dead Alkaline Battery Bounces [video]

#13

Post by jacquesm »

macromaniac wrote: post #6

It's interesting to me that using the height of the bounce against the ground for estimating the spring constant is worse than using the height of the bounce against the battery.

I don't really agree with that part of the test setup. The mass and springiness of the battery versus the slug dropped mask the fact that this is a double spring setup, there is also still the bottom of the battery contacting the base it all sits on so you can expect some of the bounce to be transferred to the battery which would not jump a whole lot. So at a minimum there would have to be a hard connection (clamped or glued in place or something like that) between the base and the battery to compensate for that.

Re: Why a Dead Alkaline Battery Bounces [video]

#15

Post by mixedbit »

They could go further with the experiment to check if a material of which the battery content is composed matters or if the stiffness of the content is the only important factor.

They could for example check how bounciness changes when a battery is filled with a gel-like substance which could then be frozen.

Re: Why a Dead Alkaline Battery Bounces [video]

#17

Post by mdda »

JosephRedfern wrote: post #9

The method has even been patented! http://www.google.co.uk/patents/US5567541

The patent was drafted very generally, but seems to focus on the volume (rather than elasticity) of the internal components. OTOH, it would be great if it were even more generally drafted, since its priority date is in 1995. 1995+17 = 2012, so the world is now wide open for innovation in this area, unimpeded by patents (IANAL).

Re: Why a Dead Alkaline Battery Bounces [video]

#18

Post by simias »

dblacc wrote: post #16

What would the inside of a recharged battery look like I wonder.

It's not the same technology and I wouldn't recommend tearing a lithium battery apart to look inside. Actually, I wouldn't recommend tearing apart any kind of batteries, lots of nasty stuff inside.

You can find plenty of videos on youtube showing you the process, for instance: https://www.youtube.com/watch?v=BliWUHSOalU

Re: Why a Dead Alkaline Battery Bounces [video]

#19

Post by junto »

simias wrote: post #18
dblacc wrote: post #16

What would the inside of a recharged battery look like I wonder.

It's not the same technology and I wouldn't recommend tearing a lithium battery apart to look inside. Actually, I wouldn't recommend tearing apart any kind of batteries, lots of nasty stuff inside. You can find plenty of videos on youtube showing you the process, for instance: https://www.youtube.com/watch?v=BliWUHSOalU

After watching that it made me think that lithium batteries could be turned into a weapon on a plane by terrorists.

Assuming that they are that easy to accidentally short them out.

Should they not be a banned from being taken in the cabin?

Re: Why a Dead Alkaline Battery Bounces [video]

#20

Post by namtuots »

haar wrote: post #7

I think one of the bits I liked most was "Romeo (Retired Old Men Eating Out) Club" - looking at its website it seems like quite a large thing over there. I know that my Grandma goes to something similar (restricted to just tea and bingo), but it makes me wonder if a similar organisation exists in the UK; a lot of the older folk I know just aren't very social any more, simply due to the fact that their social groups h…

http://www.menssheds.org.uk/
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