Help-Custom Pack batteries.??

[evilknight007]

Hi Ppl.
 I have got  10 individual  NiCd 1.2V 3000mAh(sub c size) batteries for my robot. i wasn't able to find a holder for the
batteries . Can anyone help me in suggesting a effective way to pack this batteries in to two packs .??
 
Will soldering the wire leads to the battery terminal affect its reusability .Or is there a better way ?

 I remember seeing a link which said how to custom pack battries but was dumb enough not to bookmark it .

Thank u .
 

[jabberwocky]

A fairly decent and neat way to pack the batteries together would be a piece of heat shrink tubing.  Take at a look on the McMaster-Carr store for heat-shrink and it'll come up with some various sizes.

As for soldering the battery terminals together, i can't comment.  I've always used batteries that fit into a holder, or already have connectors attached (which happen to be soldered anyway, but i expect it wouldn't be as severe as my soldering  )

[Admin]

Set your soldering iron heat up to max. The batteries absorb the heat really fast so if your heat is too low, you will never get a good bond.

[jabberwocky]

Set your soldering iron heat up to max.

Maybe i could do some savage soldering then!  Is it ok to do this high temp soldering to all battery types?

[Admin]

Ideally you don't want to apply any heat at all to the battery as it can denature chemicals, create gasses, etc.

Heat takes time to travel. Since your battery contains large amounts of metal, it can absorb heat in a short period of time. It is possible for it to absorb heat as fast as you apply the heat, meaning the temperature stays too low for solder to bond.

Remember that heat is not temperature! It is possible to have lots of heat and still be cold (or vice versa).

You would end up keeping your iron on the battery longer, with more distributed heat, resulting in more heat damage.

If you set your iron to really really hot, the temperature jumps really fast at a point location so you can solder really fast. By the time the heat starts to get absorbed by the battery, you'd already be done.

The one disadvantage to a high temperature is that you can damage the soldering iron tip much easier - so use a tip you don't care about.

(hope that made sense, this is stuff that mechanical engineers learn to calculate/optimize as an undergrad)

[JonHylands]

Also, in addition to what Admin said, get some flux, even if the solder you are using is flux-core or rosin-core. Make sure the things you are soldering are really clean, and pre-tin the wire you are soldering to the battery ends. You do this by coating the wire in flux, and then heating it up and applying solder to it, until it is coated with solder. It will work better (and is much easier to do) if the solder is already on the wire, so you don't need three hands. Hold the battery in a vise, so it can't move around while you're soldering it.

As well, after you clean the battery terminals and before you put flux on them, take a piece of fine sandpaper and score the surface a bit - the solder will stick better, but only if the surface is really clean. After you sand, clean it again (preferably with alchohol), and then apply some flux.

Make sure the iron tip is heating both the wire and the battery, and make sure the solder flows properly onto the battery surface - you don't want a glob of solder that is only lightly stuck to the battery. You can usually tell by looking at the edge, where the solder meets the surface - if it overhangs the surface, it probably isn't a good joint. If it flows down to a form a ramp from the surface, you've got a good joint.

- Jon

[Admin]

Good call Jon! totally forgot to mention that . . .

One additional point, don't forget to clean the flux after you are done - it can cause corrosion. Just read the flux container for further instructions.

[Rebelgium]

These tips are all I know there are, so I can't add aythin ...

I really think it would be a good idea to take all the tips mentioned by admin and JonHylands and permanently place them in the battery tutorial, imho.

[Admin]

Good call! Ill add that in this weekend (if not tonight).

Jon, any objections to me copying you word for word (perhaps just changed 10%-ish)?

[evilknight007]

Tat really helped guys . 
My word i have never seen a forum this active!!!  .Keep rocking guys .

[JonHylands]

Not at all - go right ahead...

- Jon