abufletcher

Again...Hmmm.... I started the charging at the settings we've discussed here and after 41mins. the charger changed the status to END. The readings were 197mA, 2387 (mAh?), and 4.197V...on a 5000mAh 3.7V battery. And I don't know what that 197mA is supposed to tell me.

Seems wrong. Very wrong. []

CanDo

If the final voltage is near 4.2v for your pack, the charge is complete. Most new packs come slightly over 1/2 charged. I believe the second number is the mAh and the first number is the charge rate in mA. According to the numbers, the charger was putting in a small charge, but the final voltage and mAh seem very typical of charging a new battery pack.
-Les-

wyo69cowboy

My Feedback: (2)

Since the battery you have is factory hard wired in parallel, it is as noted before, (2) 2500mah 1 cell (3.7V) packs, and the charger just "sees" a single 3.7V 5000 mah pack. Not sure what the 197mah number would have been, but your time and 2387mah numbers sound about right for charging a new pack. I've ordered many packs from HobbyKing before, and they are always right around 3.8V per cell at initial charge...

wyo69cowboy

My Feedback: (2)

I think you're fine; 4.2V is fully charged on a LiPo cell. Sounds like your charger worked perfectly [8D]

abufletcher

Why doesn't it charge to 5000mAh? The typical advice with NiCD batteries is that if the pack isn't charging to at least 80% of the full capacity, there's something wrong with the pack. Also do LiPos charge much faster than NiCDs? I guess I'm used to using a "trickle charge" for my NiCDs on my other simple chargers...and in that case, I'm typically charging them overnight.

TFF

Because LIPOs are completely different chemistry it has different handling characteristics and one you get to take advantage of is faster charging. The one you have to be careful about is fire. I believe the 2387mha is what it had to add to the battery to make 5000mha. It is telling you how much needed to get to the topped of of 4.2V. Seems about right if it was approximately 1/2 charged when shipped.

rgburrill

From what you say in your posts I totally agree that you should never be allowed to have any electronics   Before you do anything else read, read and read some more.  And some of those answering should join you in class.

Sorry to be harsh.   But really, there are some very basic things you need to know when working with batteries, especially LIPOs, that if not done correctly can cause very serious damage.  And miss-soldering wires is one of them.  How did you get talked into buying a 3.7V battery without the proper cwiring and connector in the first place?  You should know that EVERY connector loses voltage and the higher the current the higher the loss.  With only a single cell you should always have the wires directly connected to the cells - and usually you should have the correct connector at the other end installed by the manufacturer.  And you don't balance a 1S battery, no matter how many P you have.  Balancing is needed to insure that one battery in a series of LIPOs does not go dangerously low or NEGATIVE.  That just cannot happen with parallel batteries - all the cells MUST be at the same voltage.

Lastly, I hope you get a LIPO charging bag before you try to charge it.  That will provide a lot of protection if the battery decides to burn up, melt, or explode.

abufletcher

I appreciate the straight talk! I suppose I talked myself into getting this particular battery since it was cheap...and I was having a heck of a hard time finding any other 3.7V 5000mAh pack. If someone can point me to exactly the battery I do need, I'd be thrilled. One with a dean's connector already on it would be great.

As far as waiting to charge the battery...well...too late for that. It's already charged. Apparently. Maybe it's be good enough for an engine/glow system test (on a test stand) this weekend. I don't, by the way, intend on using this battery in any model.

abufletcher

I want to say again, how much I appreciate all the responses here in such a short time. I feel like I've gone from being a complete and total idiot just a few hours ago to maybe, just maybe, knowing enough to carry on.

wyo69cowboy

My Feedback: (2)

You're learning, and learning is fun, right? At least that's what I've heard... Soldering is a skill which is valuable, and I still struggle with it at times, even though I've practiced a lot Good tools and good technique help. Putting the end you need on a battery is no big deal; I'd guess 50-75% of the cheap chinese packs get their connectors changed, because most of them don't come with Dean's or imitation Dean's anymore, or have a variety of connectors.

The readout on your charger shows what it actually "put in" to the battery, i.e. 2387mah. In other words, it put in about 48% capacity, which would be about right for a battery shipped with the partial, storage charge. Someone else could chime in, as I'm not sure on charger efficiency, but 2387mah is not exactly what the battery took, because some of the energy is lost to inefficiencies in the charger/system.

C rating is just the capacity of the pack in amp/hours, vs mah hour rating the pack reads. So 5000mah divided by 1000 (milli) =5.0 amp hours. 1C means the pack theoretically should supply 5amps for 1 hour. Most lipos now will support 2,3 or more C rate charging, so yes, you can charge much faster than a nimh or nicad You could charge at 2C (10amps), 3C (15 amps), etc, but for safety's sake, a 1C charge is fine. The reccommendations you're getting to use a charge sack (a ceramic pot or old ammunition box work well too) are good advice as well.

saramos

Someone commented on the hard case in the photo of the charger and battery. These are designed for use in ground RC vehicles. They provide protection against debris strikes, but at the cost of weight. The added weight is not a big issue on ground vehilces, but could be a significant issue with air vehicles. The extra weight could help in balancing a plane if weight is needed, but would be counter productive if the battery is mounted on the heavy side of the balance point. Also, if the discharge rate is high, (as if the battery was being used to power a motor) the hard case could also limit cooling which could cause shortened battery life, damage, or even in some rare extreme condition a fire.

Ron C

My Feedback: (35)

Lets not talk about stupid, tell ya what I did back in my early 20s , I used a cutting torch to cut a 3 in piece of flat bar in two, turned the torch off, took off my gloves , then reached down and picked up the hot piece of flat bar, well duh then while still hurting I looked around to see if anyone saw it

abufletcher

This hard pack battery with its awkward connectors sticking straight up out of the top will only ever be used on an engine test stand. And it was chosen for two simple reasons: 1) It was cheap ($20) and 2) Hobby King is on the same side of the Pacific as Japan so I figured shipping would take too long. I needed a LiPo pronto to do the initialization and testing on my Microsens GLOW-LP7 and GLOW BALANCER. This is reputedly the best glow system available. The GLOW-LP7 provides all the usual glow system adjustments as well as some nice additional safety features. The glow balancer monitors all seven glow plugs and provides additional current to any that are low (typically the "wet" bottom cylinders).


Because we all know that having someone see you doing something stupid is much worse than actually doing it! Speaking of (other) stupid things, I once superglued both hands to the inside of one of my models. I live alone.

PropsnWings

My Feedback: (9)

In your pictures, while the cinder block is a good idea... the fire extinguisher is not. You will not be able to put out a LiPo fire, let alone be in the same room if it does "go off" . Or maybe I should say, it is not advised to do so.

I myself am new to LiPo's this last year, and I am no expert, but you will be fine, if you dont push hard at charging them, dont drain them beyond the cutoff, and just treat them like they are eggs.
<br type="_moz" />

straitnickel

[quote]ORIGINAL: abufletcher

I actually managed (somewhat successfully) to solder on a dean's plug BACKWARDS. Not the + to the - sort of backwards. I mean I soldered the connecting wires to female side of the plug! Seriously, there should be a poster with my face in every hobby shop saying: Do not under any circumstances sell this man electronics!

[:@]
[/quhaha lmho
I almost did that once

byrne1157

Here is a suggestion for you. Go to the closest flying club or field, with all of your equipment in a box. Ask people there if they have had any experience with lipos, lipo chargers, etc. You may find some people that are willing to give you some hands on training. <div> As an experienced electronics tech, I will give you the following info.  the mah figure(for example 5000mah), is the maximum amount of current the battery can deliver. 5000milliamperes per hour. the c rating is a multiplier.example: 20c x 5000mah= 100amps . the number of cells determines the voltage of the pack 1s=3.7 volts nominal. cells that are fully charged are usually 4.2 volts. So, if you have a battery that says 2200mah, 3s, 45c, it would be 3s=12.60volts fully charged. It will deliver up to 99amps continuous. I, personally never drain my lipo batteries below 3.3volts per cell, before recharging.  I don't run my batteries at amp draws that exceed the continuous rating. this keeps the battery cool and healthy. I don't charge beyond the mah rating. example: a 22mah battery I charge at 2.2 amps. Todays chargers are pretty smart, and if you follow directions, you should have no problems. I use lipos for power in my electric planes, for power to receivers in my fuel powered planes, and in my transmitters. It shouldn't matter where you purchase lipos, or what connectors are on them. If you need to change a connector, do them 1 WIRE AT A TIME!  This will prevent a short, and a large problem. Good luck, if you are not clear on any of this, pm me....</div>

abufletcher

That all seems reasonably clear at this point. Again, I don't ever (ever) plan to fly electric and so will never need a large multi-cell pack for a motor. And considering how delicate LiPos seem at this point in time, I wouldn't personally use them to power either the Rx or Tx. Seriously, can you imagine buying a home telephone that came with a warning that it might possibly burst in to flames and should be kept at least 10ft away from anything flammable? No thanks! [:'(] For Rx and Tx, I'll continue to use NiCD or NiMh. Unfortunately, there seems no way around LiPos for the onboard glow system.

The photo below shows the whole chain of the Microsens onboard glow system. (Note: I've replaced that ugly fat banana plug on the ground cable and added the proper connector. The LiPo battery connects to the deans plug. The red cables are the seven individual glow cables.) The next challenge is to position all of this on my test stand. Actually, the engine already has about 1-2 hours of run time, so at this point, I'm just testing the glow system.

geezeraviation

My Feedback: (3)

Dont look now but your phone (cell or portable land line) more than likely has a lipo battery in it already.
Doc

abufletcher

Doc. I don't know how to tell you this. But maybe you can already guess...I don't have either. [8D]

abufletcher

But really, when people (and manufacturers) stop recommending that LiPo batteries be charged in a ceramic jar, special pouch, or on a concrete surface, when they are as safe to use and charge as the batteries in my Nikon DSLR and Sony Camcorder, that's when I'd be willing to switch to LiPos for Tx and Rx power.

So here's the whole megillah!

byrne1157

Wait i minute. You telling me that you are afraid of a lipo battery fire, even after all of the safe charge/discharge cycles all of the world has had, but you're going to fire up that glow motor, with a lipo battery next to the fuel? Just sayin....

abufletcher

Yeah, that is pretty silly, isn't it. But if the LiPo explodes, it doesn't much matter where it is on the test stand, right?

This is just an initial attempt to situate everything on the test stand given the lengths of the wires and cables. I had been thinking that I would be able to tuck most of the electronics into the wooden box, but the glow cables aren't long enough. The engine itself runs fairly clean since it's down to 5% oil (as recommended after the break in) and I've got the exhaust collection ring installed now. So other than some "spitting" from the carb, I don't imagine there will be much mess.

Still, I'll continue to refine the installation.

abufletcher

One more battery question...Tx this time. I'm looking for replacements for the 9.6V 700mAh "square pack" batteries that came with my Airtronics radios (RD8000, VG6000). I've found this battery from CERMARK but I'm confused about the connector. My Tx batteries have just two wires (black and red) going into the connection (and there are only two pins in the Tx). I understand that the other wire is the ground wire, but would I just go ahead and order the packs with the Futaba/JR/Z connector?

http://www.cermark.com/products/Sany...%2C-FK%29.html

Also I'd prefer a Tx battery with a higher capacity (say around 1000mAh) maybe like this one:

http://www.cermark.com/products/Sany...%2C-FK%29.html

abufletcher

The Sanyo pack on Tower Hobbies doesn't come with a connector:

http://www3.towerhobbies.com/cgi-bin...&I=LXFE02&P=ML

By the way, THIS is what a Tx battery should look like! Forget those primitive shrink-wrapped packs of AA batteries soldered together, gramps! If it's good enough for every modern camera and camcorder on the planet, shouldn't these modern batteries be good enough for our transmitters

http://www3.towerhobbies.com/cgi-bin...&I=LXJYN9&P=ML

abufletcher

I currently have three types of chargers:

1) Hyperion EOS0606i
2) Hanger9 SureCycle
3. Hobbico RC Multi-charger (two of them)

The Hobbico chargers, which don't have any fancy features other than a switch to change the charge rate, handle 99% of my needs. It uses simple and inexpensive charging harnesses with banana plugs on the charger end with a simple jack for Tx and a usual battery connector for the Rx. Simple.

The Hanger9 has a discharge function for both Tx and Rx and displays "data." But the STD/JR polarity switch seems like a disaster waiting to happen. If fact, it may already have happened with one of my batteries and/or one of my transmitters. The Tx connection is a standard jack, but the Rx connection has three wires (black, red, white in that order) on the connector and I've just realized that my only still functional Tx battery (1100mAh Cadnica/Sanyo, purchased here in Japan) has two wires (red and black) and that there is no way that the red wire on the battery can align with the red wire on the Hanger9 charger. The switch is very easy to accidentally hit and difficult to see on the all black box. And if it's the case that at one setting the + current would be flowing through the black (or white?) wire, while the - current is flowing through the red one, that would seem like an invitation to disaster.

Finally, the Hyperion. I bought this to charge LiPos. But it can also do NiCD, NiMh, LiFe, and lead batteries. But connecting batteries seems to be a major hassle. It requires fat 12swg wires for output and I have no idea how I'd set this up to plug in normal NiCD Rx or Tx batteries. Most of my Rx batteries are built into my scale models and difficult to remove so I just charge though the extra connector on the switch. I also normally charge the Tx through the jack. The Hyperion seems designed to charge batteries sitting right next to it.