Thunder ac6 set 5a but charges at .1 -.2a?

[Lava Crawlah]

I have thunder ac6 charger and im charging ecopower 3s 30c 5000mah lipo. Heres my problem, i set up as balance charge, 5amp, 3cell.. As it is charging i check voltage per cell which is even or close to each other, AMPS is low .1 -.4 fluctuates, voltage is normal and mah seems normal... My charger has a saftey 120 min timer, this 3s battery hits the timer, and shuts the charger off. But my mah is below 4000 and voltage is normal 12.58v and each cell are at 4.19-4.20v..But lipo works normal in my truck... So the question is,is my lipo fully charged? is my lipo or charger not functioning right? When i charge my 2s 5000mah lipo it charges it at 5a when charging and it takes lil over an hour to charge and the mah peaks at 5000 when done vs. my 3s 2hrs to charge..Anyone has experience this? Thanks.

 

[Charlie-III]

Balance charge may be a lower rate than what you want until the cells look good to the charger.
Also, a balance charge can take longer than 2 hours @ 1C rate, I would just start the charge again until the pack is full.

 

[SINister]

You can either turn the timer off or increase the time limit.

 

[Olle P]

4.20 per cell means it's fully charged! (And the charge current automatically drops as the battery approach that level.)
You need to drain it to 2.8V/cell if you want to use all 5Ah.

 

[Trubble]

..........voltage is normal 12.58v and each cell are at 4.19-4.20v. So the question is,is my lipo fully charged?

4.20 is the voltage of a fully charged LiPo cell, yes it's done.

........im charging ecopower 3s 30c 5000mah lipo. But my mah is below 4000........

That's fine, you shouldn't be using any more than 80% of your total capacity anyway. 4,000 mAh puts you right about where you should be.

When i charge my 2s 5000mah lipo it charges it at 5a when charging and it takes lil over an hour to charge and the mah peaks at 5000 when done vs. my 3s 2hrs to charge.

All indications I've seen is that the AC6 is a 50 watt charger. 50 watts divided by 8.40 (voltage of a fully charged 2S), is 5.95238ish amps, so no problem hitting the 5 amps you set it at. Same 50 watts divided by 12.6 (voltage of a fully charged 3S) is only 3.96825 amps. Since your charger can't pass along the full 5 amps, your battery will take longer to charge. Balancing also takes longer.

As it is charging i check voltage per cell which is even or close to each other, AMPS is low .1 -.4 fluctuates,

LiPo chargers use a CC/CV program, or Constant Current/Constant Voltage. At the start of the charge cycle, its on Constant Current, so the amps stay as close to what you selected as they can. Once the battery voltage comes up to a predetermined level, the charger switches over to Constant Voltage so the LiPo doesn't over-charge, at this time the amps usually drop down to the .1-.4 range like you saw. Sounds like your charger is operating like it should.

 

[Meatwad]

Agreed, 4.18-4.20v per cell is fully charged and that you'll get closer to your 1c charge rate when closer to fully drained (-3v per cell) and also the time/mah limit can be adjusted in the ac6.

 

[dentonmac]

The balance charge goes in to like a trickle charge mode (like Trubble said), and you will see the amperage drop when it get close to full charge.

The way it was explained to me that I understood (I need pictures, not numbers). It is like filling a bucket with water, you can get the bucket all the way full with an eyedropper (balance mode). You can't get it full to the top with a fire hose. Regular and fast charge are like a firehose, just pounding the charge in there (not bad, just a different process). Where as the Balance charge pounds it in there to a point then slows the process down to get it all the way full. Hope that makes sense.

But, like mentioned before, I look at the voltage per cell to indicate when I am done or close. I always balance charge my lipos, yes it takes longer, but I have found that my batteries run better for more cycles. You sound like you are doing things correctly.

Really the most important thing I have found with Lipos is to not leave them laying around for weeks fully charged. I also have that same charger, good little unit. The storage mode works well for talking the battery to a good level for storage.

 

[Calderwood]

Different chargers use different algorithms to switch from CC to CV. It sounds like your charger has a very "safe" algorithm. I know that my buddies China charger charges a pack way quicker then my Hyperion when they are both set to the same charge rate. I believe my charger switches to CV sooner thus creating the 1 - 1.5 hour 1c charge where as his charger stays CC longer and finishes much sooner. I may be completely wrong since these are purely guesses.

 

[Lava Crawlah]

Thanks guys for the good info! 8)"thumbsup"