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Batteries & Chargers Discuss Li-P, Li-Ion, NiMh, Nicad battery technology and the chargers that juice 'em up!

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Old 03-03-2011, 04:47 AM   #1
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Default Charging LiPos inside the airplane

Most electric RC "pundits" will tell you to never to charge LiPos inside the model.
However, in reading electric conversion articles by Greg of www.gregcovey.com I see that he often charges his LiPos inside his airplanes. I get the impression that he is a very knowledgeable guy regarding these matters, so I was just wondering... Any comments on his charging methods?

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Old 03-03-2011, 04:49 AM   #2
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I have kept this pretty much outta the press, but I am guilty of doing just that.

I have charged many times with the cells in the plane.

My Corsair, Cessna, Cap Maniac, and 33% Yak are all gas conversions, and do not have 'happy' battery access.

They generally are a PITA (Pain in the Access) to get batteries in and out. Charging in the plane often means 2x the flying because of charging at the field.

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Old 03-03-2011, 05:27 AM   #3
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Nitro Blast, does a particular charger or technique make this a more reasonable or safer method? In other words, do you do anything special or different when you charge inside the airplane?

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Old 03-03-2011, 05:44 AM   #4
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Originally Posted by Henry111 View Post
Most electric RC "pundits" will tell you to never to charge LiPos inside the model.
However, in reading electric conversion articles by Greg of www.gregcovey.com I see that he often charges his LiPos inside his airplanes. I get the impression that he is a very knowledgeable guy regarding these matters, so I was just wondering... Any comments on his charging methods?
I'm not a Lipo guy, only experience is with the A123 cells. They can not catch fire, and can be charged in the model without problems. (Yup, I tried it. Blew the cells apart, zero fire. )

From what I've been able to determine, many (but not all) Lipo disasters resulted from a charger mix up when recharging the Lipo.

I've just picked up the Cellpro Powerlab 8 charger. This unit (as well as other brands of chargers) directly connects to the individual cells of your battery pack during the charging process to absolutely verify the type of battery, and number of cells your battery has.

So, using one of these updated chargers should reduce the chances of a charging disaster on your battery pack. Would I try charging a Lipo in the model with this Powerlab 8?? Probably not. Just being careful.

When we can start flying again around SE Wisconsin, that Powerlab 8 charger will be used to charge a 6S4P A123 pack, that will be configured as a 12S2P pack during flight. The charging current has been set at 20 Amperes. The battery power source for the Cellpro 8 charger is a pair of 120 Ampere hour deep cycle marine batteries connected in parallel.
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Old 03-03-2011, 09:16 AM   #5
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Many of the horror stories are from the early days before we learned about balance charging. Balance charging is relatively safe.

But having over the years watched a couple of very smart scale models, owned by "very knowledgeable guys", turn themselves into piles of black ash I still don't do it myself. Fortunately I don't own any models with very difficult battery access and mostly I prefer to just swap batteries to keep on flying. If I only had one battery with difficult access I'd probably also be tempted to push the charging speed too and that's not a good idea either.

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Old 03-03-2011, 10:48 AM   #6
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If a Person knows what they are Doing, and Has a QUALITY Balance Charger, and does Not Charge a Lipo over 1C, I think they will be Fine to charge a lipo in a plane, At your own Risk Charging A123 cells in a Plane with a Quality Charger Should be ok too, But Here is where the Problem IS, MOST Rc Pilots are not very well trained with the use of Chargers for lipos, they dont buy the best Quality Chargers, and Many Dont Understand what a C Rating is in terms of Charging a Lipo, and may over charge a lipo, that may Cause problems and someone may burn their home down, due to a Lack of Proper Lipo understanding and Cheapy Charging Equipment.

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Warning!!!, Warning!!!
It was Sunday, the 14th as(like) at 8 p.m., the CHARGER was plugged loading LiPo's battery(sink) it(he,she) was not marking load full still(yet), we put in agreement to be going to buy a LUNCH to do of having dinner in Overcome You I remembered(reminded) the battery(sink) and it is commented to my lady, we are not late mas I believe(create) of 15 minutes, We come and my family I wait for myself in the car to open first I and they were entering rapidly to cover of the cold, when I opened one fixes for the mirror of the room that the smoke was going out below the door of the bedroom that the CHARGER was plugged, there was light, I was rapidly and opened the door, the locked up smoke I stick in the face and I could not see anything, I had to go out to seize air, immediately seize the telephone and report to 060 while it(he,she) was looking for something with which to throw(add) water, it(he,she) shouts my wife who was asking for aid, lower the lever of current and between(among) (it(he,she) was bringing a deaf lamp with me, not because, I never use her …) I ran to the bedroom and opened again the door (this door is closed alone) again the smoke was not leaving me to see anything, Fan the water and listen to the hiss of the fire when it(he,she) wants to go out, I went out to seize again air and listen to my wife me to shout driven to despair that already it(he,she) was not entering, she(it) saw the big smoke from the house of face and he(she) was thinking that not tape-worm I marry to risk, I notice that the heat was not so intense and I thought that the fire scarcely was seizing force but being not able to see, I come a person that I did not know wherefrom come in with a hose and his(her,your) covered face and it(he,she) started spraying water for all sides while I continued fanning water where wise that the loader was, the smoke started vanishing and we manage to see the flame, we her(it) extinguish and extract the furniture that was catching fire, I was feeling badly, was bringing disgusts and the head was hurting(grieving) myself, But with desire of continuing up to assuring me that the danger had happened(passed), I opened the window of the bedroom and now if they came scarcely a policeman's(police) patrol and later the firemen, they assured us that the danger had happened(passed), recommended to me to take great water and to walk, this night I did not sleep, the whole clothes were impregnated with smell of smoke as well as the armchairs and the beds, but thanks to God we were with Health.
The battery was in the Miss Hydro 1.5

Sorry for my English

Jesús


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Old 03-03-2011, 11:04 AM   #7
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Originally Posted by Henry111 View Post
Most electric RC "pundits" will tell you to never to charge LiPos inside the model.
However, in reading electric conversion articles by Greg of www.gregcovey.com I see that he often charges his LiPos inside his airplanes. I get the impression that he is a very knowledgeable guy regarding these matters, so I was just wondering... Any comments on his charging methods?

Bottom line is, Unless your a Very Very Knowlageable Person with Lipo, and have Quality Balanceing Chargers, Dont do It

I may be getting Older, But I Refuse to grow Up I am Having to much Fun to Grow Up LOL
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Old 03-03-2011, 02:57 PM   #8
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Originally Posted by Henry111 View Post
Nitro Blast, does a particular charger or technique make this a more reasonable or safer method? In other words, do you do anything special or different when you charge inside the airplane?

Henry,
It is my usual practice to charge below 1C anyway, so no there is really nothing 'special' or different that I do when charging in the plane other than making sure the plane is set marginally away from everything else.

I dont charge 'in the plane', in the shop, or under the hood of my truck. When I do charge in the plane, I do not leave the plane un atttended, and check the charger often.

I consider my plane a 'fire safe' container.... If it catches fire, its a safe distance away from everything.

I use a pair of Triton chargers, and a single Thunder Power.

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Old 03-03-2011, 04:42 PM   #9
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So I think the question is - in all of your LiPo charging how many fires have you had. The ONLY issue with charging in the plane is the destruction of the battery and the plane (could be very expensive).

I for one have never had a LiPo fire. In fact my ONLY fire has been with NiCad cells (yes that is right!) when my TX battery door popped open, the battery fell out, disconnected itself from the TX. Then it hit the pilot station (cement). That caused a direct short of the pack (freak hit for sure). After the pack hit it "bouced" over to the dry grass. The heat that direct short created started the shrink wrap and then the grass on fire.

TaDa!

So ANY battery can cause a fire, does not matter the type, cell chemistry, safety, vents on cells etc. They store vast amounts of power and that energy can be suddenly converted to fire.

Mike
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Old 03-03-2011, 07:35 PM   #10
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following quote by Mr Mugen with over 8,000 rcu posts ...

I have 8 planes with Lipo's burried in them. I use an extension for the balance ports and charge normally. Been using lipo's since they became available without a mishap. It is a good idea to have them where you can see them if possible. I like to peek at them from time to time while charging.....not sure why but.... In fact I still have TP's first series of lipo's without balance ports and they all work fine still.

Most will say DO NOT do this. I am not most. Making sure you never charge over 1c is the biggest thing. I usually charge the ones in the planes at 80% of 1c just to be extra safe.


... following quote by Greg Covey(rcu electrics moderator) ... 3.3.11



The assumptions when charging LiPo packs in a plane are as follows:
  • Common sense is required.
  • You use a safe balancing charger like the FMA Cellpro series.
  • You are at the field charging in an open area, not at home with your family.
  • You do it only when needed, like in a scale plane that has no real access to the packs (e.g. TWM Ultimate, H9 Corsair)
The goal here is to balance safety with necessity. There are some beautiful scale models designed for glow engines where the fuel tank is buried inside the fuselage. When converting these models to electric power, providing easy access to the battery packs sometimes requires a significant amount of craftsmanship to cut a hatch while retaining the required strength in the fuselage. I have found it easier to install the batteries prior to a weekend event and keep the plane assembled until packing up.


... following quote by blvdbuzzard 3.3.11 from high deserts, CA

I have (2) planes I charge the battery in the plane. I have to take the wing off, unplug the ailerons, flaps, then undo the straps holding the battery. Total pain. I can reach the plug in the cowl, so I charge it that way.

Only problem I see, is "IF" and I do mean "IF" something happens and I need to pull the battery quick, I can not get to it.

I had a problem with my 60 sized trainer I converted to "E" power. I have (4) 2650 3s lipos, I connect them for a 5300 6s configuration. Well, being a human, I plugged one of the (3) "Y" harnesses in wrong and melted (2) of the lipos. They were under the hatch in the nose of the plane, so they were a little easier to get to. If they had been in a plane with the wing on, plane would have gone up in flames.

We can cause anything to go wrong if we loose focus for just a second. I have changed the way I plug the harnesses in so I do not think I will make the same mistake twice.
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Old 03-04-2011, 12:06 AM   #11
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Default Not most...

Originally Posted by Swift428 View Post
following quote by Mr Mugen with over 8,000 rcu posts ...





... following quote by Greg Covey(rcu electrics moderator) ... 3.3.11







... following quote by blvdbuzzard 3.3.11 from high deserts, CA
Nice meeting another guy who is "Not Most!"

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Old 03-04-2011, 03:25 PM   #12
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Nice meeting another guy who is "Not Most!"
Thank You!

Much of our hopefully 'better' knowledge comes from others that we regard as being trustworthy. Like You i see the value in pickin other brains no matter how much me thinks me know. Fact is we can learn a lot from those (at first glance) that we disagree with ... may even be 'better' knowledge.

When you author an article the content may in large part be due to the input of others. OK, alright ... ENUF!
________________

There is no problem charging through the discharge connector at a charge rate of even 1.5C as long as one understands the mind/unique chemistry and bouncing voltage levels during charging of say a series wired LiPo, and at least has an inexpensive cell checker. In fact it is actually better to charge through the discharge connector for a couple reasons. For the most part balance charging through the smaller white connector is for those that don't really understand the unique temperament of a LiPo, and like to see twinkling lights that give them a warm cozy secure feeling.

If a LiPo can withstand a continuous discharge rate of at least 12C, then it can withstand a charge rate of 1.5C when charging via discharge connector. The idea that one has to charge at 0.80C is only necessary when charging a BIG BERTHA LiPo through the balancing connector with its smaller wire size. And then depending on how big BIG Bertha is an 0.80C rate via balancing connector may be too high of a rate.

Better to always charge through the discharge connector. Even though some may consider this unbalanced charging it is still balanced charging because the cells are wired in series. It is only unbalanced charging if you don't have quality lipos, don't have a cell checker, discharge to LVC of 9.0v instead of 9.5-9.7v(3S - 3.2v per cell) or 12.0 instead of 12.8v(4S - 3.2v per cell), and believe everything you read (and a couple other reasons).

Charge my relatively balanced 3S lipos (only after restful nap) to 12.55 volts through the discharge connector at 1.5C charge rate. Then top off each cell individually via the balancing connector at 0.80C until they each have filled capacity to 4.2 resting volts.
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Old 03-04-2011, 07:54 PM   #13
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Default Balancing connector access

Originally Posted by Swift428 View Post
Thank You!

Much of our hopefully 'better' knowledge comes from others that we regard as being trustworthy. Like You i see the value in pickin other brains no matter how much me thinks me know. Fact is we can learn a lot from those (at first glance) that we disagree with ... may even be 'better' knowledge.

When you author an article the content may in large part be due to the input of others. OK, alright ... ENUF!
________________

There is no problem charging through the discharge connector at a charge rate of even 1.5C as long as one understands the mind/unique chemistry and bouncing voltage levels during charging of say a series wired LiPo, and at least has an inexpensive cell checker. In fact it is actually better to charge through the discharge connector for a couple reasons. For the most part balance charging through the smaller white connector is for those that don't really understand the unique temperament of a LiPo, and like to see twinkling lights that give them a warm cozy secure feeling.

If a LiPo can withstand a continuous discharge rate of at least 12C, then it can withstand a charge rate of 1.5C when charging via discharge connector. The idea that one has to charge at 0.80C is only necessary when charging a BIG BERTHA LiPo through the balancing connector with its smaller wire size. And then depending on how big BIG Bertha is an 0.80C rate via balancing connector may be too high of a rate.

Better to always charge through the discharge connector. Even though some may consider this unbalanced charging it is still balanced charging because the cells are wired in series. It is only unbalanced charging if you don't have quality lipos, don't have a cell checker, discharge to LVC of 9.0v instead of 9.5-9.7v(3S - 3.2v per cell) or 12.0 instead of 12.8v(4S - 3.2v per cell), and believe everything you read (and a couple other reasons).

Charge my relatively balanced 3S lipos (only after restful nap) to 12.55 volts through the discharge connector at 1.5C charge rate. Then top off each cell individually via the balancing connector at 0.80C until they each have filled capacity to 4.2 resting volts.
Regarding your last sentence:
This means that one would also have to have access to the balancing connector in addition to the discharge connector???

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Old 03-04-2011, 08:19 PM   #14
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This means that one would also have to have access to the balancing connector in addition to the discharge connector???


So, how does my meticulous fillup invalidate Greg’s input(e.g. FMA Cellpro) or the way another competent electric flyer balance charges their onboard LiPo with a “balancing charger” that isn't a Cellpro? Does my more meticulous method(the way I 'balance charge') really change the overall game plan here ... that being some brain storming for safest onboard balance charging of LiPo(s)? I don't think so.

That said, I agree that the charge port with Cellpro is the way to GO! If I had a Cellpro instead of Vision Peak Ultra, then the Cellpro would be doing the meticulous topping off fillup instead of me. I get some satisfaction as a "tinkerhead" topping off each cell according to each cell's unique temperament so at LVC each cell is within 0.10 volts of each other. Well, to explain how I top off each cell (e.g say ... 4.20v, 4.22v, 4.21v 'resting' volts) isn't really necessary for this thread

Greg said ... "You use a safe balancing charger like the FMA Cellpro series."
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Old 03-04-2011, 10:32 PM   #15
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Good stuff, Swift!

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Old 03-04-2011, 11:56 PM   #16
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Originally Posted by Swift428 View Post
That said, I agree that the charge port with Cellpro is the way to GO! If I had a Cellpro instead of Vision Peak Ultra, then the Cellpro would be doing the meticulous topping off fillup instead of me. I get some satisfaction as a "tinkerhead" topping off each cell according to each cell's unique temperament so at LVC each cell is within 0.10 volts of each other. Well, to explain how I top off each cell (e.g say ... 4.20v, 4.22v, 4.21v 'resting' volts) isn't really necessary for this thread
I've watched my Cellpro Powerlab 8 charge my 6S2P A123 cells, both with the Cellpro's individual cell voltage display, and my 6 channel home made individual cell display microcontroller operated meter (accurate to 0.5%).

Interesting, while the Cellpro 8 charges the battery, each cell is identical in voltage. And, at the end of the charge cycle, each cell levels off, and stays at exactly 3.65 Volts DC, the proper value for the A123 cells. And, the Cellpro voltage indication is identical to my home made meter.

And when each cell is exactly 3.65 Volts DC, the charging current drops off until the charge cycle is complete.
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Old 03-05-2011, 07:48 AM   #17
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Charging a lipo at .8C or 1.5C or 3C makes no difference as far as fire safety goes.

The reason lipos catch fire is over voltage - not charge rate.

Charging an out of balance pack - even at .1C - will still cause a fire if any cell gets much over 4.5 volts.

Thats why you should always use a balance charger.

Charging at low rates WILL NOT prevent a battery fire if the pack is out of balance.

Charging at low rates WILL NOT balance your lipo pack. Only a balancing charger can do that.

At the same time, charging modern cells at HI rates will not cause a fire IF the cells are kept in balance and not allowed to go above 4.2 volts.

I think I need a signature.
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Old 03-05-2011, 10:26 AM   #18
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Originally Posted by Swift428 View Post
Better to always charge through the discharge connector. Even though some may consider this unbalanced charging it is still balanced charging because the cells are wired in series.
Sorry but that statement is simply wrong. Charging series connected cells with a constant current and no regard for the state of the individual cells is the very definition of unbalanced charging.

What you really mean is that it is fairly safe PART charging that way provided that you don't attempt to fully charge like that but always terminate the charge early and then complete the charge by balancing individual cells.

I know you said later that that was how you did it but that was after making all these dogmatic and dangerous comments about it always being better to charge through the discharge connector i.e. without balancing.

For those of us who don't want to mess about part charging with one charger, stopping the charge and completing it with a balancing charger it's still the case that balance charging is MUCH safer than unbalanced charging via the discharge connectors .

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Old 03-05-2011, 12:19 PM   #19
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My,my,my.

OK I do not charge LiPolys in the aircraft normaly due to the simple fact that all of mine have battery hatches. I did charge a 3S A123 inside of my MUS for over 500 times and at 20A rates but thaat was LiFePO4 not LiPoly.

I do however routinely charge LiPolys at between 3 and 12C, in my house, in my shop and on the tailgate of my Blazer at the flying field.

I use more expensive balancing chargers, I balance most every charge and I observe the charges except while the aircraft is actually in the air. During these charges I glance over to the pits a couple of timres per 5 min. flight.

I have charged LiPolys thousands and thousands of times. I have beta / field tested LiPolys,chargers,balancing chargers, balancers, data loggers, and other misc. RC equipment for many manufactures,developers,verndors.




http://www.wattflyer.com/forums/show...44&postcount=6

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Old 03-05-2011, 05:42 PM   #20
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Originally Posted by slipstick View Post
Sorry but that statement is simply wrong. Charging series connected cells with a constant current and no regard for the state of the individual cells is the very definition of unbalanced charging.

What you really mean is that it is fairly safe PART charging that way provided that you don't attempt to fully charge like that but always terminate the charge early and then complete the charge by balancing individual cells.

I know you said later that that was how you did it but that was after making all these dogmatic and dangerous comments about it always being better to charge through the discharge connector i.e. without balancing.

For those of us who don't want to mess about part charging with one charger, stopping the charge and completing it with a balancing charger it's still the case that balance charging is MUCH safer than unbalanced charging via the discharge connectors .

Steve
You were more direct than I was but I agree 100%

Originally Posted by everydayflyer View Post
My,my,my.

OK I do not charge LiPolys in the aircraft normaly due to the simple fact that all of mine have battery hatches. I did charge a 3S A123 inside of my MUS for over 500 times and at 20A rates but thaat was LiFePO4 not LiPoly.

I do however routinely charge LiPolys at between 3 and 12C, in my house, in my shop and on the tailgate of my Blazer at the flying field.

I use more expensive balancing chargers, I balance most every charge and I observe the charges except while the aircraft is actually in the air. During these charges I glance over to the pits a couple of timres per 5 min. flight.

I have charged LiPolys thousands and thousands of times. I have beta / field tested LiPolys,chargers,balancing chargers, balancers, data loggers, and other misc. RC equipment for many manufactures,developers,verndors.




http://www.wattflyer.com/forums/show...44&postcount=6

Charles

Thanks again Charles!

I think I need a signature.
Larry
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Old 03-05-2011, 07:37 PM   #21
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Good stuff, Swift!
May we quote some of your comments?
When Henry111 says, “Good stuff” and “May we quote some of your comments” the odds may be at least 50/50 that like slipstick he may take some of my comments out of context as examples of what not to do. It’s always safer to go with the ‘balance charging’ herd mentality, even if that mentality is somewhat misinformed.


Originally Posted by slipstick View Post
... making all these dogmatic and dangerous comments about it always being better to charge through the discharge connector ...
I only know of a couple inexpensive LiPo balance chargers that charge through the balance connector(see photos below). However, the Cellpro and ALL other more expensive, trustworthy balance chargers charge through the LiPo discharge connector. Let me say it again with even more “dogmatic” emphasis. The BEST Way and PREFERRED Way when adding mAh capacity(charging) to a LiPo pack is via the discharge connector NOT the smaller multi-pin connector.

The balancing act during charging via the smaller multi-pin connector is more of a resistance holdback of voltage. There’s some legit minds that believe it’s actually better to let the cell voltages bounce around a little (unique lithium temperament) during the charging process … instead of trying to be so controlling--like a Blinky. A Blinky is more of a control freak than a level-headed overseer.

Yet, some that read your reply will get the definite impression that they should never add mAh capacity(recharge) via the LiPo discharge connector. Maybe, you are still of the old school that even had printed instructions stating … “Never charge a LiPo through the discharge connector.” There are a couple good reasons for adding mAh capacity(recharging) a LiPo via its discharge connector. Do you know what they are?

My Vision Peak Ultra AC/DC charger is actually capable of a balancing act, and I can discuss that with you. Would you first please tell us which of the two LiPo chargers shown below(or another brand) you're using that charges only via the smaller multi-pin balancing connector with NO connection hookup whatsoever to your LiPo battery discharge connection.


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Old 03-05-2011, 08:11 PM   #22
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Originally Posted by Swift428 View Post
However, the Cellpro and ALL other more expensive, trustworthy balance chargers charge through the LiPo discharge connector. Let me say it again with even more “dogmatic” emphasis. The BEST Way and PREFERRED Way when adding mAh capacity(charging) to a LiPo pack is via the discharge connector NOT the smaller multi-pin connector.

The balancing act during charging via the smaller multi-pin connector is more of a resistance holdback of voltage. There’s some legit minds that believe it’s actually better to let the cell voltages bounce around a little (unique lithium temperament) during the charging process … instead of trying to be so controlling--like a Blinky. A Blinky is more of a control freak than a level-headed overseer.

I've just picked up a Cellpro Powerlab 8 charger. This charger can recharge a battery either through the balance connector, or by the battery power leads. Or, it can use both the balance connector AND the power leads. Your choice.

As far as my A123 packs go, I've watched the Cellpro charging process using both the balance and power leads. The Cellpro charger keeps all cells at the same voltage during the charging process, eventually leveling all of them at the same exact final voltage at the end of the charge cycle.

Agreed, those "Blinkys", as far as the A123 batteries go, IMHO simply doesn't work. And I've damaged a 6S2P A123 battery two years ago while using the blinky. The discharge and charge voltage curve on those A123 cells is just to flat for any discharging type of blinky balancer to work.

The Cellpro charger is not a discharge type of balancer, it is apparently an "additive" type of balance charger. Much different from a blinky.
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Old 03-05-2011, 08:26 PM   #23
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Originally Posted by kyleservicetech View Post
This charger can recharge a battery either through the balance connector, or by the battery power leads. Or, it can use both the balance connector AND the power leads. Your choice.
Under what conditions would you(and/or instruction manual) recommend that a LiPo(e.g. 3S,4S) be recharged ONLY through the multi-pin balancing connector with No connection/hookup whatsoever to the power(discharge) leads? ... Instead of being recharged by most everybody via the power(discharge) connector with the LiPo multi-pin connector in the Cellpro balancing port as manual recommends.

Page 13 of Cellpro Powerlab 8 says ...
If the pack has both heavy discharge wires and a balance connector, connect both to PowerLab
8 (good for any charge/discharge current):
Note: Best practice is to connect balance connector first, then connect
discharge wires. -13
I can't find any recommendation for situation when LiPo should be charged only via balance connector when pack has both discharge connector and balance connector. Maybe slipstick only adds mAh capacity(charging) into his lipos via multi-pin balance connector from an inexpensive LiPo charger (see previous photo of slipstick's possible charger).
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Old 03-05-2011, 09:07 PM   #24
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Originally Posted by Swift428 View Post
Under what conditions would you(and/or instruction manual) recommend that a LiPo(e.g. 3S,4S) be recharged ONLY through the multi-pin balancing connector with No connection/hookup whatsoever to the power(discharge) leads? ... Instead of being recharged by most everybody via the power(discharge) connector with the LiPo multi-pin connector in the Cellpro balancing port as manual recommends.

Page 13 of Cellpro Powerlab 8 says ...

I can't find any recommendation for situation when LiPo should be charged only via balance connector when pack has both discharge connector and balance connector. Maybe slipstick only adds mAh capacity(charging) into his lipos via multi-pin balance connector from an inexpensive LiPo charger (see previous photo of slipstick's possible charger).
The same page 13 of Cellpro Powerlab 8 says ...
"The balance port accepts a 9 pin Cellpro balance connector, which supports packs up to 8s. For charge/discharge rates up to 3A, you can use just the balance connectors as shown below"

IMHO, running "up to 3 Amps" through those little Balance connector pins is pushing those pins just a little. And, I'll be using both the high current and the balance connections on all of my 6S2P A123 packs, and the one 6S4P A123 pack for my Hacker A60-16M motor.
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Old 03-05-2011, 10:44 PM   #25
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IMHO, running "up to 3 Amps" through those little Balance connector pins is pushing those pins just a little
and yet many swear that their servos draw more than 10 amps. thrugh leads and connectors that are even worse.

Yes the FMA balancing leaeds / connectors can indeed handle 3 amps. just fine and in fact even 4 amps.
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