Solder directly to battery and pcb?

[Rothman]

Just wondering if it is safe to solder wires directly to the positive tip and pcb of a lithium ion battery. Working on a new high cap, small size mod and need to make this work. I can't seem to find a website that sells single, pre tabbed, protected batteries. Will I blow myself up attempting this? Any advice?

 

[BobTheKlown]

If it were me, and this is just me, somebody with more real world experience in EE, or who builds their own rc batt packs, might feel very differently, I would not want to solder direct to a batt both because I would be afraid of shortening the battery's lifespan by overheating it, and, to an only slightly lesser extent, the possibility of blowing it up.

I would think a conductive copper tape or something similar would save about the same amount of space and be both safer and make it easier to change out the batt when it dies...

 

[duby]

I gotta back up bob here. I wouldn't be too comfortable with soldering to a batt. It can be done, but you should be extremely careful. I wouldn't do it.
Thin copper tape/tabs sounds great, you can also solder to high temp neo or samarium magnets and use those as connectors.

 

[WillieB69]

I gotta agree with the first two. I'm no electrician or any kind of wizard when it comes to this stuff but I know heat and batteries don't mix. High heat and batteries DEFINITELY don't mix. Plus, who knows what you could be doing to your protective circuit?

 

[WillyB]

Clean the battery ends real good and apply some flux. Pre-tin your tabs and use a large, hot iron (30W ain't cutting it). You want to be real quick and not take more than a few seconds.

 

[Kobudo]

Having made my own RC packs in the past, I would say everything above is true.

My take on it, batteries fail, and it's not worth the effort. If space is an issue, you can make your own extra-thin connectors out of sheet aluminum from a hobby store (mine came from Hobbytown). The stuff I use is no thicker than the wall thickness of a cereal box, and is easy to cut with scissors. This will save more space than a soldered tab does.Though I do still recommend a spring on the negative end to assure a good contact.

 

[Shad0w]

Clean the battery ends real good and apply some flux. Pre-tin your tabs and use a large, hot iron (30W ain't cutting it). You want to be real quick and not take more than a few seconds.

Has always worked for me. 40 watt iron fully heated and tinned tip, flux on battery connector and apply heat to solder connection for no more than 3 seconds. Cool with compressed air.

 

[AttyPops]

Has always worked for me. 40 watt iron fully heated and tinned tip, flux on battery connector and apply heat to solder connection for no more than 3 seconds. Cool with compressed air.

Guess it can work.... If WillyB/Shad0w said it will work, it will work. The down side, of course: they can "go boom" if they get too hot. I agree with Kobudo; why would you want to? Li batteries have a limited life-span anyway. It's easy to use a battery contact. Then you can replace the battery.