hey guys, how come my 4010 duo is going from the charge current phase to the balance phase of the charge dropping all the way down to .4 or .5 amps? i got this charger specifically for the faster balance current! and its fricken as slow as my damn $35 budget orion charger. Do I have to up the end current percentage rate? Default is 10%. how do I get the advertised 1.2a balance current? or is this rating relative to the size and voltage of the lipo?

How fast your charger can charge your cells all depends on the condition of your pack. If each cell has the same voltage during charging then the faster they will finish. The only reason why some packs takes forever to charge is because the charger is spending a significant amount of time at low current charging, trying to balance charge the pack so all cells are at the same voltage.

Balance CURRENT has nothing to do with balance CHARGING. Balance charge basically takes into account the cell voltage and limit the charge current. Say one cell reaches 4.2v and the others are at 4.0v. The charger will start reducing the charge current to prevent the cell from going over 4.2v until all cell is at 4.2v.

Balance current is only used in the balance function, it equalize the unequal voltage of each cell in a pack. Say one of the cells in your pack is at 4V while the others are at 3.85, it essentially discharge the cell that cell until the voltage matches the other cells. The higher the balance current the faster it balances. In your case, the 4010 has 1.2A of discharge current to drain the cells in the pack so each one of them are the same

It is the way how a Lithium battery behaves while charging, that is why it is called CC/CV

When the battery is empty it has a lower voltage than the charging voltage, basically connecting 2 different levels of voltages together it is a shortcut. Then the Constant Current will step in.
When the battery is on voltage with the charging voltage the current will slowly drop further but the Constant Voltage will stat on its value..

Because the balancing current is much lower than the charging current then at the end of charging when the charging current has become very low the working of the balancing current will take the overhand.

ohh so the end phase (balance phase) of a charge cycle cant be sped up or adjusted? and the 1.2a rate is only done in a balance cycle? i never need to use balance function. i always balance charge... i cant believe theres no control for speeding up the end phase of balance charging. a lot of youtubers are "advertising" balance current rating for how fast the battery finishes charging. (balance charge of course)

The end balancing process is determined of how equal the cells are. If one is not in a top condition as the other(s) then the balancing will take more time.

There's actually 2 different currents going on with a balance charge. The main one is how much current is provided to the pack as a whole through the main + and - terminals. The second is the balance current going through the balance connector. I think the charger only reports the main current.

If the 4010 is getting stuck balancing for an extended period then the pack is not healthy. What is the IR showing on the individual cells and what is the voltage per cell at the point it starts the CV part of the charge cycle?

to my insane shock both cells were ~25 ir !!!
didnt even think that was possible for a healthy pack. i only have 7 cycles or so on it. its the protek Lihv 2s 2200 receiver pack.

Receiver packs have significantly higher IR than race packs.

why is that?

Smaller surface area inside the cell, smaller wires connecting the cells.

Plus, since Tx and Rx packs only have to deliver a tiny fraction of the power of race packs, they are usually produced from far lesser quality cells.