Forming a recent NiMH purchase on the Hitec X4 and other computerized chargers.

Ed writes me about properly forming a recent NiMH purchase.

Hi Dave,

I recently bought one of the FDK Twicell 6.0V 5-cell 2000mah NiMH AA Flat Pack and would like to try it in one of my airplanes . I read all your comments about this battery pack and I have the HiTec Multi-Charger X-4 and not sure what is the best way to charge it. The charger is fairly new in my collection and I am still learning the best way to use it any thoughts?

Thanks,

Ed

Ed,

The best way to do it on most computerized chargers is:

General procedure,

1. Go into setup, make sure the mah limiter and time limiter are both off.

2. Put charger in PB mode, yes for Lead acid.

3. Set charge rate to 100mah, any more will ruin the battery eventually.

4. Set voltage of battery to 8V

5. Start charger.

If it refuses to start, set voltage to 6V and let it run a minute or two, the go back and restart with setting at 8V

“Generally” Eneloop’s (Twicell’s) come to you about 1/2 charged. So, the hole your filling is about 1000mah. (Hole * 1.4) / charge rate in mah = time in hours. 14 hours in this case.

What we are doing with the procedure above is tricking the charger into functioning like a dumb wall wart where it will just plod along indefinitely until we disconnect the battery.

The best practice would be to connect the cells to a dumb charger that charges at 50mah for about 30 to 40 hours and is the ONLY method for which I would ever consider warranting a pack. People try to break in new batteries in peak detection modes all the time which is the cause of my slightly “acidic” warnings against such acts on my website. One issue is there are no makers of chargers like that that I know of in the hobby world today. The last one (Sirius) seems to have become inactive. The best chargers to own for this forming purpose at this time are an ACE DDVC, ACE Digipulse or Sirius Pro-Former. Should you run across one at a swap meet or on Ebay, snap it up.

Dave

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Tin Whiskers

I’m not a big fan of the gradual banning of lead. Sure, I love kids and all that. However, the enviromentalists take everything too far with what they clothe in “for the greater good” arguments. It’s really an anti-capitalist movement. And, I’ve been trying for a long time to figure out what is pro-job about being anti-capitalist.

I can understand how lead in paint which breaks down slowly over time, becomes chips which get smaller and eventually turn into dust. It makes sense not to put lead in paint because we’ll eventually breathe it. However, no matter how hard I try to kick the dirt around on the floor, electronic circuits soldered with leaded solder or lead free solder don’t jump into my mouth. Maybe the difference is hard for some to see? What is it like to wield the power to ban an element on the perodic table?

So, on to tin whiskers…..

RoHS is an EU (European Union) directive that has become enforced law. RoHS means “Restriction of Hazardous Substances”. The problem is little consideration given to what is a Hazardous use of a substance and what is not. I don’t hear reports of children eating circuit boards or solder joints in wires for example. Is it about health and public safety, or about creating a portal by which government and regulatory bodies can exert command and control over huge industries and the influx of goods into a country?

Since the EU has issued RoHS directives, lead has been removed from most solders and from the tinning on electronic leads. Pure tin is now used for almost all electronic component lead tinning. Over time it forms whiskers of tin which are thinner than a human hair. They are only one crystal in thickness and they reach out and touch leads of other components. It’s often the reason why today’s TV’s and other electronics (including our RC gear) doesn’t last as long as yesterday’s. Failure of expensive satellites have been attributed to lead-free tinning of leads causing tin whiskers. It’s our punishment for letting the “zero tolerance crowd get traction and get this nonsense pushed into law all over the world. When you get a chance, in any way possible, do your part, do something about it.

Here are some great links, good reading and photos of our gift from the enviromentalists, “tin whiskers”.

I’m still looking for examples of children that were poisoned from eating circuit boards and wires.

Find lots of tech article links at: NASA Tin Whisker Homepage

An excellent blog post by Steve Smith: Tin Whiskers

1.4 Million Results on Google

As long as possible, you’ll always be able to get “real” solder from Radical RC: Solder Pastes & Supplies

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