Guys, we are waiting for your reviews! It is a pity that I do not see support HiLV (4.35) and LiFePO4… Why does the Liitokala chargers in the engineering line (Lii500, Lii-400) not add support for these cells, аnd in the line of cheap chargers (Lii 402, Lii202) there is support. Strange logic.
Only difference I see with the (in my opinion very good) LII-500 Engineer is . . . . . . new display, new looks. Is all.
Cheers,
Nico
Can it load longer cells than lii-500?
I could not find the detailed specification. Judging by this photo, 21700 is supported, but 21700 with protection will no longer fit
Looking forward to receiving mine, my only concern is that i have an original too and dont like that they changed the polarity. I mean I never liked how you put the cells in backwards on the original but stick with it now! Probably gonna mark them with red/green paint or something.
Yep, me too. Not sure if you noticed Fred, but it was a Pre-Order. Fulfillment is supposed to be by 18 June. Ward supplied me with that info. I think June told him. 
Where have you found where you can buy on pre-order at an interesting price?
- Support for 21700 cells.
- More spacing between slots.
- 2A max charging current.
- no 300 mA charge rate.
thanks
Going to wait for reviews, myself. If they’ve sorted the Lii-500 niggle of only charging to 90% on NiMH, then I’m interested 
What? The 500 only charges Nimh to 90% capacity? I never heard of that. Where can I read more about it?
I have not noticed that phenomenon with my Lii500.
In HKJ’s review:
Search for “Charge NiMH”; there’s a bit that says: “The termination look like a voltage termination and without filling the cell completely. Generally it looks like the capacity display is a bit high for NiMH cells.”
Looking at the graphs, it seems to be falling short by about 10%. The charger shows about 1900mAh - 2000mAh, but HKJ’s equipment only shows about 1700 mAh - 1750mAh going into the cell. The effect appears to be consistent across all four slots.
In his conclusion, HKJ again mentions that: “The charger is very good at charging LiIon, but stops a bit early on NiMH.”
I’m wondering whether the person who wrote the charging algorithm forgot to account for the pauses while it’s measuring the cell voltage.
Hmmmm…. Thanks for the info Phlogiston. I’ll have to look at/check mine out more closely. 
Now I understand why my Ikea Ladda AA 2450 mAh batteries last considerable shorter in my Logitech Mx Mouse, compared to using disposable batteries. Hope they fixed it with Lii-500S.
The Lii-500 uses multiple Ni-MH end of charge detection algorithms, including voltage termination. Modern Ni-MH cells are not overcharge tolerant, thus if the charger decides to use voltage termination for some cells or in some cases I concur with this.
I recently measured the capacity of 11 Turnigy sub-C 4200 cells from a dismantled drill battery pack whose owner left the battery without charge a full day or more after fully depleting it (something which caused one cell to get reversed, die and get shorted). Cells had less than 10 cycles. Each cell was tested 2 times in slots 1 and 4, 22 tests total. Final average capacity was 4189.27mAh. None of these got a voltage termination in any case, for sure.
Saying the Lii-500 undercharges Ni-MH cells is a fallacious generalization. And in any case, what I said above. 
I am a little disappointed in the #8 “feature”. You can only use USB out if running on a/c power, not able to charge USB devices off of the cells in the charger.
The main problem of using external or removable cells to feed a power bank boost circuitry is additional cell contacts and slot resistance burden, causing voltage drop, lesser efficiency and overall making the boost engine's life harder. If slot rails were made tight, high quality and were to remain always clean the idea would make more sense. On top of this lesser drain and/or small cells cannot provide enough power output to make the power bank function work reliably. When you tally up all of this, plus general user's ignorance and easy availability of standard power banks, I can understand why the power bank function is dropped from the charger.
:-)