everydayflyer

If you want full details then please use this link:

http://www.rcgroups.com/forums/showp...16&postcount=1

I will post a few attachments here on RC U for those who just hate to leave here.

Ultra Min Stick with Hacker 30/16 ,APC 13X6.5E and 3S A123 ,8 min. flights and 5 1/5 min. average charge times. Over 140 cycles on pack and no change in performance. Average charge amps. 18.5 as calcultaed . 1.7 Ah per flight / 5.5 min. charge times.

Charles

guver

My Feedback: (325)

Here's what I think is nice: Chargeing in no time flat does not encourage "unattended chargeing" besides being a time saver.

everydayflyer

188 flights ( 167 ZiP charges) on the 3S A123 pack and still going strong.

everydayflyer

Ziping right along.


Charles

guver

My Feedback: (325)

How about trying to ramp up the initial charging speed so the average is higher?

Higher at start, maybe lower at finish. A very smooth, but quick ramp up and down according to capacity might be blistering fast , yet not heat the battery any more.

everydayflyer

That would require a lot more than a simple length of wire being used as a means to limit charging rate. The whole idea here is to be able to use a charger which cost next to nothing.

How fast do you want? IMO a 5 1/5 to 6 1/2 minute charge is plenty fast and the batteries do not get more than slightly warm, much cooler than during the discharge.
Charles

guver

My Feedback: (325)

No specific time in mind, it is nice to know the practical limit though. 5 minutes is a long time if you're "waiting"

everydayflyer

249 flight and a 6% capacity lose from flight #40 and Dsch # 251.

In fact it is really closer to 260 discharges as I did not count any of the prior graphed discharges.


Charles

coro_sk

I highly appreciate Your work. It encourages me to stop being afraid of high current charges...
I am surprised that green voltage line is a bit higher (voltage) than red. Is it repeatable or caused by just an ocassional difference in something? (e.g. different current, temperature or something like that) ?

everydayflyer

Full details in post at RC Groups but short answer is Dsch 250 was one day after being Zip charged at field and Dsch 251 was following recharge on Balance Pro HP .
pack was also warmer following discharge ,recharge and second discharge.


Snip from RC Groups;

Charles

coro_sk

Thank You very much,
I mistakenly did not notice that Dsch 251 was right after charge. That explains all, of course.
So, it says, that for ordinary use, user can drive this cells hard also during charge, and charge them at any power his charger is capable. Especially, occasional flyer like me - I will grow much older until I will fly single pack 250 times. :-)
This cells are simply great. I also hope that smaller A123 M1A 1100mAh ones, will behave the same way.

Antique

My Feedback: (4)

Pardon my ignorence but what is a "ZIP" charge ?

dirtybird

My Feedback: (5)

No need to pardon your ignorance. People that coin new terms should explain what they mean.

everydayflyer

Well Zip charging is not really a new term in fact it is so old that it comes under the term.

All things old are new again.

To break it down. Zip line , lamp cord, two conductor flat extension cords are all one in the same.

Way back in the early days many of us used different lengths / gauges of this wire to drop the available current from a single cell Pb 2 volt battery to light a 1.5 volt glow plug and years later to charge Nicad packs for our R/C cars,trucks,boats and even a very few of us for electric power airplanes.
Believe it or not once upon a time in order to fly / run R/C you had to build your own equipment.


The very first post in this Thread contains this link:

http://www.rcgroups.com/forums/showp...16&postcount=1

which i advised to be used.

As I post here on RC U , RC Groups and WattsFlyer it is very time consuming to post complete deatils to three seperate boards.

Not to step on to many toes but I find that many only read the last one or two post and very often never bother to even read the OP. I also find that many never bother to use a link which has been provided.


Charles

dirtybird

My Feedback: (5)

Not to step on any toes but I followed your link several times and I felt I was stepping in the middle of a lot of confused details. Zip cord was a name applied to extention cord by some seller some time ago. He never bothered to specify what he meant. Now You are using the term to describe a method of charging apparently using lamp cord. But you don't say how long or what size wire to use. Who knows what zip cord is?
Is it any wonder others don't know what you are talking about?
Actually the zip (Lamp) cord I have used is a relatively low resistance wire. It needs to be to get a large current to the lamp without too much waste of power.
If you need resistance in the line you might be better off using chromel-alumal wire - Thermocouple wire. I think it can be had at Radio Shack.

everydayflyer

From my first post:
Snip from first post at linked Thread
First attachmment there show complete setup in operation .Second attachemnt shows Zip (lamp) cord ga. and length.
I later found that that lamp cord was mis labeled and I posted a correction in the text of first post.

Note : If 20 ga. Zip (lamp) cord is / was used then no real harm done as it would only reduce the charge rate and increase the required charging time.

As I included the statement :
First let me say that if you are not an avid DIY type and do not understand such then do not try this.

I feel I gave fair warning that this was not going to be a step by step how to project.

FYI Many on RC Groups have built such chargers and are extremely happy with them.


Notice! Once again this is for charging 2300 mAh A123 Racing / DeWalt cells in a 3S configuration. The VPX 1100 cells were not available at the time I started using this charging means. The charge rate from this setup would be much to great(high) for them.


Charles

everydayflyer

277 flights ,254 Zip charges and still going strong.

Charles

decay

I'm sorta confused myself. Is ZIP type wire a special kind of wire or are you
just useing the risistance the wire offers to limit the current?

Commercial RC equipment has been being manufactured since the 1960's
Possibly even eariler, if you could afford it!

everydayflyer

From post # 14


True and I stsrted flying R/C in 1963.


Not sure of your point however my point of using a Zip charger for a 3S A123 pack is the ability to charge a pack in less than 8 minutes with a setup which cost next to nothing.

I have many expensive chargers one of which is a $200 TP-1010C ( I was a Beta tester and in fact I am the one primarley responsible for the A123 upgrade for it) and even it is slower than Zip charging.


Charles

everydayflyer

Here is the latest improvement to my Zip Charger.

It is a solid state circuite which terminates the charge at set point which I have adjusted to 11.4 volts for my 3S A123 2300 pack.

DIY construction Thread for cut off device here:

http://www.rcgroups.com/forums/showt...22#post8844692

Charles

decay

Just wondering, are you the guy known as Woo Hall on RCG?

everydayflyer

You sure no how to hurt a guy's feelings.
Look at my user's name. Same here,RC Groups and Watts Flyer as wll as Traxxas.

decay

Oh, I should have known

everydayflyer

450 flights logged now and all is still well.


Charles