Hello all. I have a question about something i really cant understand. So now ive changed from old Q30s to HG2s - got last two triplets like a week ago. Put in to Opus charger and it show 3.53V and charged at 0.5A....took a while and when they got to 4.20V it was showing about 2400mah charged......but all next recharges from about 3.7V it charged to 4.2V but showed only like 1400ish mah......so how come? Is it something how they are made or it really recharges ~1000mah from 3.53V to 3.7 or 3.8V???
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I am not positive, but I would say it really is a 1000mah difference from 3.5v-3.7v. These batteries tend to stay at certain voltages for longer than others. Once it gets so low it will start dropping off rapidly, which tells me the mah drop off will not be linear either.
I think it’s the way chargers read outs are, they display the mah’s it charged not the total mah capacity.
Most ecig mods cut off and declare the battery dead at 3.3v. There's still charge in the cell, but the cell will last longer (number of charge/discharge cycles) if you don't fully deplete it each time. Charging from 2.5v to 4.2v creates a lot more heat than charging from the 3.3v level.
The specs for MAH ratings are based on a drain down to 2.5v (full depletion) followed by a charge back to 4.2v. If your starting voltage is closer to 4.2v what your charger will show is the milliamps restored to the cell from that voltage.
It's kind of like, "How many gallons does it take to fill up a car gas tank?". It depends on how much is already in the tank.
The specs for MAH ratings are based on a drain down to 2.5v (full depletion) followed by a charge back to 4.2v. If your starting voltage is closer to 4.2v what your charger will show is the milliamps restored to the cell from that voltage.
It's kind of like, "How many gallons does it take to fill up a car gas tank?". It depends on how much is already in the tank.
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But exactly this - so lets say, you need 100liters for a full fill - you buy a new car with 10liters in it and fill it up to full, next refill when you burned down those filled in 90liters, you can only fill up 65liters now and your car is already full. Im sure my english not even close to good, but ill prolly will have to drain one triplet to 3.5 and charge then and see if i get those 2400mahs to fully charged 4.2V Nor im sure if the charger gives up right readings...sometimes it charged to 4.2v , sometimes to 4.1 or 4.15 So im sure all the cell thing is more complicated than i can fully understand
But thank you for all replies!
But exactly this - so lets say, you need 100liters for a full fill - you buy a new car with 10liters in it and fill it up to full, next refill when you burned down those filled in 90liters, you can only fill up 65liters now and your car is already full. Im sure my english not even close to good, but ill prolly will have to drain one triplet to 3.5 and charge then and see if i get those 2400mahs to fully charged 4.2V Nor im sure if the charger gives up right readings...sometimes it charged to 4.2v , sometimes to 4.1 or 4.15 So im sure all the cell thing is more complicated than i can fully understand
But thank you for all replies!
MAH readings indicate current battery state, but the MAH number a cell is rated at is calculated in manufacture from a 2.5v state. You don't really want to discharge your cells that low because it's hard on the cell to do that repeatedly. Most devices cut off far above 2.5v. In our ecig use MAH translates to relative battery life. A 2400mah cell won't run as long as a 3000mah cell in the same application, but you also have to consider Amperage ratings for a particular application.
If you are vaping above 60 watts that's a breakover point where you need to look hard at a cell's CDR (Constant Discharge Rate). As CDR rises, MAH starts to fall, so there's a trade-off in capacity and amperage draw.
The best way to judge battery condition is to measure internal resistance. If your charger displays MAH information it likely gives you an internal resistance reading. New cells on my charger are usually under 50 ohms, most are around the mid 20 ohm range. As cells age, internal resistance rises. When it hits the 200 to 300 ohm range I generally wrap them with tape and drop them off at a recycle center like Batteries Plus.
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Simply put, they don't drain from 3000 mah (what lg hg2s are rated) tp 0 mah (will never go to 0 actually, I hope...) at an even steady rate. The chart above shows that nicely. From 4 to 3.7 volts they drain more consistently then drop off more quickly. This is normal for all batteries, but different batts have different rates.
Exactly. And if a cell is rated at 3000mah that number is based on its usable charge life down to 2.5v under a test load. Draining to lower voltages puts a lot of stress on the cell. Most devices cut off at 3v, so when we charge the MAH rating the charger gives us is less than the design numbers.
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That is a funny discharge graph, very funny actually. 35 - 43C discharge rate curves in a, let's
say, 2.7Ah minimum specced cell? Well, that means 94.5 - 116.1A discharge ratios, which is even higher rating than the BroScience V2 
8000mAh Mooch tested long ago for an April Fool's day. No comments. 
Cheers
That is a funny discharge graph, very funny actually. 35 - 43C discharge rate curves in a, let's
Cheers
Indeed...I think it is impossible to have a cut-off at around 23 degree and discharge with so much C...it looks more like egyptian hieroglyphs without having a Rosetta stone....
Okay, thank you all for help here. I did get a higher recharged mahs when charging from 3.6V - was around 2000mahs....so all is fine and looks like last ~1k mahs is in those 3.5V-3.7V and around 1.6k mahs from 3.7 till 4.2 Kinda stupid now when im thinking, that ive never did try to "stop and think" why the hell so random readings and where all those mahs gone
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