Capacity Variations Same Charger - Different Slots

Zebretta · 2018-12-27T16:46:23.000Z

I have an AccuPower IQ338XL that retails for around $47.00
Even though it’s pretty good and I can’t complain, I can’t really vouch for the “Accu” part
Seems to me it’s priced a bit high.

The reason I think it can demand $47.00 is because it’s probably THE ONLY hobby charger that can do discharge cycles, has an LCD display and that can do 4 D-Cells

I’ve noticed that the capacity I get for a given battery depends on which of the 4 slots I run the test in.

The difference I get from Slot 1 to Slot 4 is usually around 100mAH, but can be as much as 200mAH
So I guess if I want maximum capacity from my batteries I have to charge them (or at least test them) all in Slot 4……

Not a deal breaker, but it does show inconsistency.

What charger do you have, and do you experience this same thing? maybe it’s more common than I realize.

Zebretta · 2018-12-29T16:58:28.000Z

Maybe this is a rare problem?
I doubt it.

flydiver · 2018-12-29T17:20:29.000Z

Is this across all chemistries?
How do you know which is the ‘correct’ slot, or the most accurate one? Meaning what known standard are you measuring it against?
The 100-200mAh difference> for a AAA cell that’s significant. For a D or large cap 18650 it isn’t much.
For older poor quality NiMh of any size I can readily see pretty wild inconsistencies in capacity no matter the charger used.

I have seen capacity difference between charges, and between slots. This is a known issue for inexpensive consumer grade chargers. For myself, as long as no individual charger or slot shows itself to be a glaring outlier I don’t worry about it. Trying to measure rocket parts with a wooden ruler seems a recipe for frustration.

FWIW, I have a Opus, 2x Lii-500 and another one given away, and 2x Zanflare C4 with 2 others given away but all were tested before passing along. All of them worked fine and within my ‘standards’ of performance and safety. My personal pet peeve is the IR on the Lii-500 is worthless. All of them are a little erratic. Personally I get my most consistent IR results from the C4.

I also have 2 Turnigy hobby chargers. They both do all the tricks. One is pretty accurate using a Wattmeter as a measuring standard (but how accurate is THAT? ). The other is off almost 30%! Charges fine, discharges fine, screen is inaccurate as hell, but consistently inaccurate. Go figure.

Zebretta · 2018-12-29T20:22:08.000Z

flydiver:

Is this across all chemistries?
How do you know which is the ‘correct’ slot, or the most accurate one? Meaning what known standard are you measuring it against?
The 100-200mAh difference> for a AAA cell that’s significant. For a D or large cap 18650 it isn’t much.
For older poor quality NiMh of any size I can readily see pretty wild inconsistencies in capacity no matter the charger used.

I have seen capacity difference between charges, and between slots. This is a known issue for inexpensive consumer grade chargers. For myself, as long as no individual charger or slot shows itself to be a glaring outlier I don’t worry about it. Trying to measure rocket parts with a wooden ruler seems a recipe for frustration.

FWIW, I have a Opus, 2x Lii-500 and another one given away, and 2x Zanflare C4 with 2 others given away but all were tested before passing along. All of them worked fine and within my ‘standards’ of performance and safety. My personal pet peeve is the IR on the Lii-500 is worthless. All of them are a little erratic. Personally I get my most consistent IR results from the C4.

I also have 2 Turnigy hobby chargers. They both do all the tricks. One is pretty accurate using a Wattmeter as a measuring standard (but how accurate is THAT? :question: ). The other is off almost 30%! Charges fine, discharges fine, screen is inaccurate as hell, but consistently inaccurate. Go figure.

Thanks for the info Fly. Very useful.
I recently did this series of tests to compare the results from slot to slot for a given battery in my IQ338XL
To do this series of tests, I simply placed the same battery in each of the 4 slots and obtained the IR reading and repeated that 6 times per battery.
Battery 1 is an 18650 and Battery 2 is a NiMh

As you can see, inconsistency is the order of the day
Of all these results, I trust the ones from the MC3000 and SM8124A the most.