prodgodq

My Feedback: (2)

I'm interested in building my own li poly packs for my own personal use.

Does anyone have any articles or instructions on pack building? I know li poly packs can be quite dangerous so I want to be safe.

Any suggestions as to tools, supplies, etc.? I've seen the supplies for sale, but I've also seen the videos of li poly pack
"flame outs", so I don't want to try pack construction until I'm fully informed.

Any help would be greatly appreciated!

Thanks.

Red Scholefield

My Feedback: (9)

Right now I'm trying to help a guy that wants to do his own prostrate surgery. I'll get back to you as soon as I'm (or he) is finished.

Matt Kirsch

My Feedback: (21)

Your biggest challenge these days will be finding the loose cells to build the packs. Due to liability concerns, most LiPoly suppliers have stopped providing individual cells, and only supply assembled packs. Most of what you'll find are older generation cells that don't have the same punch as contemporary cells, if you find any at all.

The tabs on these cells are aluminum, so normal solder doesn't work. You need special aluminum solder. Plus, they're in close proximity to the very heat-sensitive, vacuum-sealed plastic bag that contains the cell. The soldering operation must be a quick in-n-out stealth operation.

As far as causing a fire... You aren't likely to cause a fire by just soldering the cells. If you pay attention to HOW the fires are started, it's always one of three things:

1. Overcharging.
2. External short circuit, or excessive current draw.
3. Internal short circuit, generally caused by crash damage.

The contents of the cell need to reach a certain temperature to ignite. You would certainly notice a problem LOOOOOOONG before that would happen with the heat of a soldering iron.

prodgodq

My Feedback: (2)

I thought I was asking a legitimate question here, Red. Sorry you don't agree. I'm relatively new to the RC hobby, but I've already had my fill of local and national 'experts'
who can't keep their egos in check. It's also bad for your website to irritate potential customers.
[sm=angry.gif]




quote]ORIGINAL: Red Scholefield

Right now I'm trying to help a guy that wants to do his own prostrate surgery. I'll get back to you as soon as I'm (or he) is finished.
[/quote]

Red Scholefield

My Feedback: (9)

[quote]ORIGINAL: prodgodq

I thought I was asking a legitimate question here, Red. Sorry you don't agree. I'm relatively new to the RC hobby, but I've already had my fill of local and national 'experts'
who can't keep their egos in check. It's also bad for your website to irritate potential customers.
[sm=angry.gif]

Thanks, that tells me a lot. Obviously you'r ego won't let you listen to them either! I'm sorry if my response to your legitimate question was a bit subtle. Trying to assemble your own packs based on snippets of information you can find on the Internet - unless you are planning on getting extensive training in soldering, electronics assembly, etc. , can be very hazardous. Just as it would trying to find out how to do your own surgery. You might, when you request such information, give people some idea of what skills you already posses so that they (we) might better know where to start to help you. How one explains to a 7 year old how to build something is vastly different than explaining it to an experienced craftsman. I found that instruction books and detailed plans for building a model enabled some to proceed with a minimum instructional support to successful completion (and flying) while others were totally helpless - even as adults they didn't even understand some of the words. So in the future all would be better served if you tell us where you are coming from so we can tell you how to get where you want.

Customers that I irritate probably would not understand the material on my website anyway so no loss.

Greg Covey

prodgodq,

Sorry, but I had to laugh at Red's quip because there is a commercial run for a stock broker that uses a similar theme.

On RCU, we don't condone making your own Lithium packs due to safety and liability issues.

Can we help steer you in another direction for your pack needs?

prodgodq

My Feedback: (2)

Red:

And a big thanks to you as well. I've also found all that I need to know about you.

I didn't realize that you have lots of customers to lose and are so successful, so I'm sure you won't miss my business at all.

Where I'm "coming from" might suprise you. I'm actually a functional adult who reads at the college-graduate level and is even
capable of reading a set of instructions, building a plane, and guiding it to a successful flight. I'm sorry, but it appears that you and I have no need to pursue this any further.

Have a great day.



Greg: Thanks for your help. I've always gotten a great deal of information from your reviews, and I appreciate the
advice on lipo packs. I was leaning toward not building them anyway as a result of the battery pack "flame out" videos that
I've seen posted here. What I'm initerested in are the "lower end" 3 cell packs, around 1100 to 1800 milliamps per hour in
series. I do have some cost issues to think about as my funds to persue the hobby that I love so much are somewhat limited.
My local club consists of primarily gas and glow flyers, so If you have any suggestions as to where I can find lower-cost packs,
from your company or elsewhere, I would really appreciate it.

2walla

My Feedback: (10)

Depending on where you want to use it for, you may want to look into li-ion cells. I have built a bunch of 7.4 v 2000ma packs for my mini-t and slow stik using li ion cells- you can buy them for about $5 a cell and they are slightly larger than a AA- nice thing is that you can get them with solder tabs from most wholesalers- they will put out about 6amps continuous . If you need a bit more amperage you can buy premade li-poly packs on ebay as cheap as you can buy the individual cells and put them together yourself. I am as "thrifty" as they come and the only li-poly packs I have soldered on was a brand new TP1320 11.1 that suffered a prop strike and lost a cell. Treat all lithium based batteries with respect! They can and will bite.

Good Luck!

prodgodq

My Feedback: (2)

2walla:

Thanks for the advice! I've done a lot of searching on the internet and it appears that what you've said is right. There seem to be some good packs available on ebay and here on
RCU. Kokam also makes a modular system so pack configurations can be changed.

BTW - when your TP1320 got nicked by the prop, was the pack reusable after you replaced
the bad cell? I've read that one bad cell can damage the other cells in the series.

thx for the help,
prodgodq