Results 1 to 12 of 12
  1. #1
    RC Racer
    Join Date
    Oct 2011
    Posts
    212

    Will this Charger work?

    So I don't know much about lipo's. I was going to order a few ***** 2200 mah 2s 20c lipo's and I was wondering if this charger would work. It's for my RC Heli. If not oh well I'll go out and find a new charger.




  2. #2
    RC Turnbuckle Jr.
    Join Date
    Jun 2010
    Location
    Miami, Fl
    Posts
    6,731
    that won't work, it is only for 3s, besided at 0.8 amp charge rate it will take forever to charge a lipo batt, get a thunder ac6 from hobbypartz.

  3. #3
    RC Qualifier
    Join Date
    Dec 2011
    Location
    North Florida
    Posts
    676
    NO! do NOT plug your 2s lipo into that 3s only charger, lol.

    and yeah that'll take forever to charge a decent 3s. You have to think, a heli's lipo is generally not a very high mah, so that 0.8 amp charge might charge a 800mah battery in about an hour, but it'll take for freeking ever to charge a 2200mah battery

  4. #4
    RC Racer
    Join Date
    Oct 2011
    Posts
    212
    Thanks. Problem solved. Here I come Thunder AC6!

  5. #5
    RC Turnbuckle Jr. JimmyNeutron's Avatar
    Join Date
    Oct 2009
    Location
    Alma, Michigan
    Posts
    12,316
    1,320 minutes, roughly; for a 2200mah battery.
    1,080 minutes, roughly; for a 1800mah battery.

    And if you run them in parallel, you can double that time.
    Whatever it is I just typed... could be wrong.

  6. #6
    RC Racer
    Join Date
    Oct 2011
    Posts
    212
    Hahaha Jimmie, that would definitely stink. I read in another post of yours that you can play for 3 hours and charge six batt's in an hour. This would make me; play for one hour and charge for two days. Hahahaha. To funny. New charger it is.

  7. #7
    RC Racer
    Join Date
    Oct 2011
    Posts
    212
    So as I stated earlier, I don't know a whole lot about lipos. These are the things I have heard about them and I'm hoping you guys could confirm or deny these statements.

    1. Running a lipo and only draining it half way is okay to put back on the charger.
    2. Charging times can be fast or slow and it doesn't really effect the life of the battery or how good it performs.
    3. The "C" rating is what the power of the battery is measured by instead of in volts like on a nimh.
    4. Never run the lipo dry. (completely discharge)

    So this is what I have mostly heard about lipos and I just wanted to make sure what is true and whats false so I don't ruin anything. Feel free to add anything else that you think is important. Thanks!

  8. #8
    RC Qualifier
    Join Date
    Dec 2011
    Location
    North Florida
    Posts
    676
    Quote Originally Posted by arcaptainic View Post
    1. Running a lipo and only draining it half way is okay to put back on the charger.
    I've done it a few times. Normally if I have to end a run early with a half charged lipo, it's because of broken parts, lol. Really, the half charge thing hasn't been an issue since the old NiCd days, since those batteries had the "memory effect".

    Quote Originally Posted by arcaptainic View Post
    2. Charging times can be fast or slow and it doesn't really effect the life of the battery or how good it performs.
    For the most part, that's correct. But it also kind of depends on the battery. If you charge a lipo at 1c (basically 1 amp of charge per 1000mah), a lipo will generally charge in about an hour. But many batteries can take a charge at a rate greater than 1c (3c, 4c, 5c, etc) and those can be charged at a higher amp, resulting in a much faster charge. But if you charge a battery with a 1c charge rating at a 2c rate, not only do you risk making the battery catch fire, but it's eventually going to damage the battery. But from what I've seen and heard, there's no noticeable effect (short term or long term) on the life and/or performance of the battery depending on how you charge the battery (assuming you charge it within spec), unlike NiMh packs that would eventually start showing fatigue after a bunch of high amp fast charges.

    Quote Originally Posted by arcaptainic View Post
    3. The "C" rating is what the power of the battery is measured by instead of in volts like on a nimh.
    Well, a lipo sill has a volt rating; 3.7 volts per cell (1s = 3.7v, 2s = 7.4v, 3s = 11.1v, and so on and so forth). The C rating (DISCHARGE C rating, not to be confused with the CHARGE C rating I was talking about earlier) is basically the rating at which the battery can discharge, or deliver it's voltage. Many times you'll see two C ratings; a continuous and a burst. Continuous is just that; it can deliver that amperage constantly without stress on the battery. The burst is what it can momentarily top out at, but if the draw is held there for long periods of time, the battery will begin to heat up, and if that current is pulled from it for too long, it could possibly damage the battery. This C rating goes a little more in depth as well as it ties in with the MAH rating of the battery. C always equals the capacity of the battery, or the MAH. The number in front of the C in the rating is basically saying that number x's the capacity of the battery. So let's say we have a 2000mah battery with a 20c discharge, we're basically saying 20 x's 2000. That equals 40000. Now that is not the amperage your battery can deliver, LOL! You have to then divide that number by 1000. 40000 / 1000 = 40. So that battery can deliver 40 amps of current continuously. If it had a bust of 40c, then 40 x's 2000 = 80000. 80000 / 1000 = 80. So that battery then has a burst amp capability of 80 amps.

    Quote Originally Posted by arcaptainic View Post
    4. Never run the lipo dry. (completely discharge)
    That is absolutely true. NEVER run a lipo battery on an RC (or anything else for that matter) that isn't designed for it and doesn't have a built in LVC (low voltage cutoff). If a lipo is drained too far, it will cause irreversible damage to the cell(s). 2.8v per cell is pretty much instant death. Personally, I like to keep them 3.2 or above at minimum. Some ESC's are programmable and you can change their voltage cutoff limit, such as the Castle Sidewinder SCT I run in my mini. But on a few you don't have that luxury, and are pretty much stuck with whatever the manufacturer deems is safe, most of the time 3v - 3.2v per cell. BUT, if an ESC is NOT lipo compatible and doesn't have a built in LVC and it's ran with lipos, it will continue to drain the lipo down pass the point of no return, UNLESS an external LVC module is used.



    Anybody feel free to comment or correct me on any of that
    Last edited by iamsuperbleeder; 01-10-2012 at 10:32 PM.

  9. #9
    RC Turnbuckle Jr. JimmyNeutron's Avatar
    Join Date
    Oct 2009
    Location
    Alma, Michigan
    Posts
    12,316
    ^^^
    Very well said!
    Whatever it is I just typed... could be wrong.

  10. #10
    RC Racer
    Join Date
    Oct 2011
    Posts
    212
    Fantastic iamsuperbleeder! Wow thanks a bunch.

    Another question; If I am not mistaken the VXL-3m has LVD. That being true does anyone know the cut off of that VXL-3m? Also what happens when the LiPo is "cut off" during run time?

  11. #11
    RC Turnbuckle Jr. JimmyNeutron's Avatar
    Join Date
    Oct 2009
    Location
    Alma, Michigan
    Posts
    12,316
    I think it is 3.0v per cell... I rarely ever get to hit it as my set up is good for over 1 hour run times... meaning I usually have to cut playtime short. lol

    First step is half power... then no power at all. You will feel it the second it cuts out.
    Whatever it is I just typed... could be wrong.

  12. #12
    RC Qualifier
    Join Date
    Dec 2011
    Location
    North Florida
    Posts
    676
    Quote Originally Posted by arcaptainic View Post
    Fantastic iamsuperbleeder! Wow thanks a bunch.

    Another question; If I am not mistaken the VXL-3m has LVD. That being true does anyone know the cut off of that VXL-3m? Also what happens when the LiPo is "cut off" during run time?
    I want to say the Velineon systems are set at 3v per cell (it'll shut off at 6v when running a 2s, and 9v when running a 3s), but I'm not 100% sure on that. When the ESC goes into LVC, you'll basically just loose all throttle; the truck will shut down, you'll still have steering though (or at least that's what happens with my Sidewinder). But don't just sit there and turn the steering back and forth, because although it might take a while, the servo could start sucking up enough power to bring the lipo down pass 2.8v per cell.
    Last edited by iamsuperbleeder; 01-10-2012 at 11:56 PM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •