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Thread: Lipo break-in: The how, why, and benefits of a DIY discharger

  1. #1
    Navigator PnoT's Avatar
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    Lipo break-in: The how, why, and benefits of a DIY discharger

    I've been doing a lot of reading on lipos recently and one thing that stuck out was how a few people were breaking in their batteries. Up until now I would go pretty easy on a pack for a flight or two but never had a method to know how many amps were being pulled and no foundation for what the process was.

    Breaking in Lipos are said to have the following benefits:

    1. Increased overall pack life.
    2. Volts per pack/cell are generally higher during the course of your flight.
    3. Packs are less likely to puff due to abusing them as they're broken in properly before ever being flown.

    In my eyes those three things are pretty huge and so the quest to learn more about it and how it's done is what I'm about to outline. I'd like to say upfront that all the information was taken from 3 different forums and from other users that laid down the foundation and put in the long hours to come up with these methods. My hats off to you guys and by no means do I claim to be an expert on the subject but laying it all out in a single post makes life easier =)

    Hanging around in the Ritewing and Stryker forums will inevitably get you on the right track in going fast but it was interesting to see how packs were being prepared for serious abuse. In the 100+ pages of the RiteWing build forum there were nuggets by a few guys... GryphonRCU, Moparmyway, and Murdnunoc. These guys really have their stuff together and GryphonRCU posted up a very sweet article on how to build a discharger using 12v 50w track lighting bulbs for lipo break-in.

    HERE is post 1597 on one forum and ANOTHER that has better pictures so check them out and you'll understand how much effort and work this guy has put in. I had a few questions and right off the bat he was very friendly and quickly caught me up on the entire process and this is another fine examples of how this community rocks!

    Tracking down the recommendations of these guys was not a quick thing but here it is to digest and while you're looking it over you can notice how close they are to one another.

    ----------
    GyrphonRCU: (5000mAh pack so adjust accordingly)

    1st and 2nd cycle: 5*5C = 10A
    3rd and 4th: 5*10C= 50A
    5th and 6th: 60-80A
    7th+ "Ring it's neck" 100A+

    Moparmyway:

    1st – 3rd cycle: 3-5C
    4th-6th: 10C
    7th-9th: 20C
    10+ 30-40C if so needed but not necessary

    First .......... charge a new battery @ 1"C"
    - discharge battery @ 5 "C", no more than 60% of rated mAh, then charge @ 1"C", then repeat
    - discharge battery @ 10 "C", no more than 60% of rated mAh, then charge @ 1"C", then repeat
    - discharge battery @ 20 "C", no more than 60% of rated mAh, then charge @ 1"C", then repeat
    (If your batts are 45/90 "C", then add two 30 "C" cycles before full load amp runs)
    -now you can run full rated amps and start charging @ rates higher than 1 "C" if your battery is rated for it.

    Murdnunoc:

    A good break-in practice for new batteries is to first charge them, then discharge first time at 3-5C. On a 2500mah pack, this would be 7.5-12.5 Amps. This first discharge should not go below 3.7-3.8V per cell. Do another charge/discharge cycle just like that first one.

    Then you can do another pair of charge/discharge cycles at 10C or 25A on your packs. This time you can let them go below 3.8 per cell. Your goal is to pull about 60% out of the pack. You can track the mAh taken out of the pack with your wattmeter till it gets to 1500mAh for the 2500mah packs.

    Third pair of charge/discharge cycles is discharged at 20C (50A) till you take out 60% mAh.
    Fourth pair will be at 30C (75A)

    ----------

    Now that I was clear on why and how they were breaking these lipos in I set out to buy a few items of my own and make a quick and dirty discharger.

    Supplies:
    (4) 3 Pack of 12v 50w Halogen bulbs at Lowes $8.33ea
    (2) 8 pair of Alligator test leads at Radio Shack $7.20ea
    10 gauge wire and clips I already had laying around the house.

    I took the test leads from radio shack and cut them in half because both ends have alligator clips and by doing so doubled the amount of clips I had to work with. The bare end of the lead was then crimped with a generic connector in the pictures because my brother has a thousand of them laying around. I would highly suggest using the shielded kind vs. what I have to avoid any shorting. The 10 gauge wire had an XT60 connector put on and the other end was stripped back about 4-5" to expose the bare wire. Coating the bare end of the wire in solder stiffened it up and made it easy to attach the alligator clips to them and prevents the wire from becoming frayed.

    You can see in the pictures below how things are setup. The watt meter tells me the Amps pulled, mAh consumed, and a few other things. I also have a cellulog pro 8 that is attached to the balance plug just so the individual cell voltage could be watched for added safety and for my own curiosity.





    The pictures are of me breaking in 2 new Gen's Ace 3s 2200mAh. The bulbs are pulling 4.4A each in parallel and 2.2A in series so you can get pretty damn close to the Amps you need by wiring them appropriately. If you take the time to read some of the links above you'll notice these bulbs will instantly fry at 6s so they have to be wired in series and will take 2x the amount of bulbs to pull the same Amps that a 3s will take =/

    To figure out what I needed for the new 2200s I simply did some math:

    2200mAh /1000 = 2.2Ah
    2.2Ah x 5C = 11A | 10C = 22A | 20C = 44A | 30C = 66A


    Code:
    Run    Amps      Cut-off                 Bulbs
    1-2     11     3.85 per cell              2P 2S
    3-4     22     1320mAh consumed           5P
    4-5     44     1320mAh                    11P

    Please be really careful when running these lights to avoid the massive amounts of heat and not to short them as a dead lipo is no good to anyone! Murdnunoc runs his setup on the concrete floor in his garage.

    I hope someone finds this useful and I'll try and post back with some results of how these new lipos perform. I have (4) 4S3300 | (2) 2S5300s that will be broken in this same way in the coming weeks if these go well.

    Feel free to chime in, contribute, or make corrections as needed and I'll update this first post appropriately.
    Last edited by PnoT; 9th May 2011 at 01:57 PM.
    "1.3GHz 850mW video transmitter. Warm as hell. Drains power as thirsty camel." -Rastislavko

    "At this point DL was an option, sat back and saw more feedback from buyers. Start getting good range results 12-15-17km 20-22-25km? From a $320 system??? Looks good, really good. Price drop to $269, end of story..." -Po73

  2. #2
    That's cool but to be honest I'll never do that. It's too much work for what it's worth. it also seems like the benefits are a "feeling" rather than a fact, so again all that effort for that... that's probably why so few do it.
    Then again I'd happily be proved wrong

  3. #3
    Navigator PnoT's Avatar
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    Quote Originally Posted by ZobZibZab View Post
    That's cool but to be honest I'll never do that. It's too much work for what it's worth. it also seems like the benefits are a "feeling" rather than a fact, so again all that effort for that... that's probably why so few do it.
    Then again I'd happily be proved wrong
    Most of the major manufacturers of lipos have some type of recommendation for breaking in their lipos from the factory so that in itself should tell you something. I have found some vendors have it out there in the open while others have it buried in a 200 page manual!

    You do have a valid point and I should have included some links to the lipo break-in tests that have been done by Charles and a few others that show the benefits outlined above to provide more evidence. I'll work on that when I get back from vacation next week.

    This is just one of those instances where if you're an average user it's probably not appealing as you can just go buy more cheap lipos. If, on the other hand, your pretty hardcore and want every last drop out of your equipment then this is the current recommendation.
    Last edited by PnoT; 11th May 2011 at 05:50 PM.
    "1.3GHz 850mW video transmitter. Warm as hell. Drains power as thirsty camel." -Rastislavko

    "At this point DL was an option, sat back and saw more feedback from buyers. Start getting good range results 12-15-17km 20-22-25km? From a $320 system??? Looks good, really good. Price drop to $269, end of story..." -Po73

  4. #4
    Moderator Derek_S's Avatar
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    Quote Originally Posted by ZobZibZab View Post
    That's cool but to be honest I'll never do that. It's too much work for what it's worth
    I would agree with you to that point, but I would like to maybe take the time to try it just to see if I see adifference. At the rate I am going, I see a noticeable decrease in lipo performance in about 6 months. I am having better luck with the nanotechs, but they are grossly overrated on C rating for my application, which I am wondering if that is what is keeping them healthy. I usually bought 20c 2200 zippys since i have really no application over 30amps (they should be good for 44a) but I wonder if they are actually a little overrated.

    Oh, and for the really lazy, there are chargers that can do those cycles for you. I know my cheapo can cycle, but max discharge is 1a so I cannot follow the prescribed method in that way since 1A is just too low.

  5. #5
    Navigator PnoT's Avatar
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    Quote Originally Posted by Derek_S View Post
    I would agree with you to that point, but I would like to maybe take the time to try it just to see if I see adifference. At the rate I am going, I see a noticeable decrease in lipo performance in about 6 months. I am having better luck with the nanotechs, but they are grossly overrated on C rating for my application, which I am wondering if that is what is keeping them healthy. I usually bought 20c 2200 zippys since i have really no application over 30amps (they should be good for 44a) but I wonder if they are actually a little overrated.

    Oh, and for the really lazy, there are chargers that can do those cycles for you. I know my cheapo can cycle, but max discharge is 1a so I cannot follow the prescribed method in that way since 1A is just too low.
    The nanos hold up really well believe it or not and the Gen's Ace are amongst the best out there. TP has some unreleased lipos that Charles has that beat everything he's compared them against pretty much. It'll be interesting to see what type of price premium those are going to command.
    "1.3GHz 850mW video transmitter. Warm as hell. Drains power as thirsty camel." -Rastislavko

    "At this point DL was an option, sat back and saw more feedback from buyers. Start getting good range results 12-15-17km 20-22-25km? From a $320 system??? Looks good, really good. Price drop to $269, end of story..." -Po73

  6. #6
    the genaces are good indeed, also they're super cheap
    the nanotechs aren't that good, except the high charge rate, main selling point imo

    chargers doing the cycle would be more interesting for me, if it works properly. i remember that nicad chargers would do that, for lipos of course it has to stop much earlier and so on

    are the HK cheapo any good?

    Eg http://www.hobbyking.com/hobbyking/s...idProduct=5548
    or http://www.hobbyking.com/hobbyking/s...idProduct=6478

    or http://www.hobbyking.com/hobbyking/s...dProduct=15437

    or
    Last edited by ZobZibZab; 12th May 2011 at 07:40 AM.

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    I think that I'm going to try it, perhaps a first 2 runs with 1A discharge on the charger. All you have to do is fully charge them then discharge them to storage value, then I'm going to put it on the plane and make a run without hittm max current at about 5-10C abd for a couple of flights I will try to discharge only down to 60%. It think that is reasonalbe break in, just wonder if it makes sense to do the first one.

  8. #8
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    You tend to see quite a bit of battery care in high performance areas. Eg. F5B and other similar types of flying.

    The simplest thing to do is just go easy on your new packs for the first 5 cycles, or run em through your charger/discharger.

    Then the next level I guess would be what you have laid out... but what is the difference between the above and the more complicated? I would bet it's not that much.

    One good thing you can do, especially if it's cold, is pre-warm your packs. 30c is where the performance is at and you will get longer running times and power if you start your flight with warm lipos.

  9. #9
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    Along time ago, I bought (2) 8000mah and (2) 4000mah 3S batteries. I did a simple 1C charge 1C discharge to 3.7V for each battery. I then did a 1C charge 5C discharge for them, since they are rated at 10C, I did the last break-in run at 1C charge 7.5C discharge.

    I have always charged the batteries at 1C and never take them below 3.4V.

    The (2) 8000mah batteries have over 360 cycles on them and are over 3 years old and still carry 97% of original state. (1) 4000mah battery has 500 cycles and is now showing some signs of weakening. The other 4000mah was involved in a crash and was damaged so I can't report on it, but this is also where the story gets interesting.

    I was told by a learned electronics engineer something similar to the following. The older lipos with the older chemistries benefited greatly from a initial 1C charge to maximum capacity 50% of C DISCHARGE TO 3.4V for the first couple of cycles and then would get up to around 400 cycles before they started to loose there maximum capacity, But that was only if you consistently stayed below 80% of the C rating.

    Most older lipos and almost ALL recent lipos show little benefit of Break-in if A) you charge at less the rated maximum charge, B) discharge at less than 80% of maximum C discharge ratings, and C) never drop the voltage below 3.3 -3.4V.(depends on chemistry) and only show a minor life expectancy increase with a break-in cycle if the limits above are exceeded.

    This is from a FAQ page of a lipo battery manufactures site.

    Do Li-Po batteries require a "break-in" process?
    Older packs used to need so, yes, but with modern cell matching and newer chemistries which the bigger brands all include in their manufacturing process, it isn't so much the case. However, the first cycle of the pack IS NOT the best cycle. It takes about 3 cycles to get the best performance out of the pack, and it will stay at this level for many more cycles. We have noted this happens with all discharge rates from ultra high currents to low currents.

    Batteries are like most other things, If you run the at maxim capacity your going to do some damage.

    My thinking is just use some common sense. Run you pack through a few cycles of 1C charge 50%C to 70%C discharge before flying. If you are running batteries above 80%C then your C rating on your batteries is to low. If you have to charge your batteries at 5C so you can run again right away, buy 2 more batteries and charge at 2C.

    I would like to see some real scientific proof, not anecdotal stories of the supposed benefits of break-in of present day batteries.

    Just my 2 cents worth.

    Robert
    Last edited by qbert; 26th December 2011 at 05:17 PM.

  10. #10
    could quit if I wanted to volto's Avatar
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    Thanks for posting this PnoT, but with qbert, I would like to see quantified evidence that this actually helps with new batteries before going through all that effort and extra expense.

    I do like to break in my motors, and usually use a battery to do that, and let it go all the way to LVC (set LVC to "high" on ESC), so in a way I have already broken in most my lipo batteries, since I just use whatever charged battery I see first. I have logged power vs thrust doing motor break-ins and found that it does help significantly. Of course breaking them in during flight is also an option.
    Don't steal, the government hates competition.

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