Extended battery stats question

[Mooncatt]

I got the 6,400mAh Perfine battery and have been running it the past several days. I'm also running AccuBattery and C3 Battery Monitor to compare to my OEM battery, and I updated the battery capacity rating to match the new one on both apps. The battery does last longer since my old one was going bad, but I'm not sure if the stats are correct or if this new one is defective. I actually expected a little longer time than I'm getting.

I can't upload screenshots because of the forum app, but AccuBattery is reporting the new battery is at 50% health with a capacity estimate of 3,181mAh. When charging, it never registers a full capacity charge when at 100%. I did run the battery down until it shut off, then fully charge it to manually calibrate the app, and there was little change. Deleting app data did help by clearing the old battery history, but not by much.

3C is reporting full 6,400 capacity when I charge. So one of the apps is incorrect and I'm almost thinking this one is it, especially if it's just going by the phone percentage reporting. Side note, I mostly use this app for checking voltage drops and current history, not so much for capacity.

So I guess I'm curious what others have experienced with using larger batteries and these apps. What's making me question this is my time between charges isn't quite what I expected even after letting it break in over a few days, and that it's not taking much longer to charge than on the OEM battery. Being a larger capacity, it should take a fair bit longer to charge because the charge current would remain the same.

 

[tickerguy]

It should take almost twice as long to charge for a given current level. The V20 rarely will permit more than 2,000ma of charge current (and not much more than that even under ideal circumstances with a QC3.0 charger) so it's a simple matter of time and milliamps delivered to figure it out.

It would not be the first time some Chineesium vendor stuck a bigger case on a same-size something and called it bigger. I suggest WEIGHING both batteries (stock and "extended") with a reasonably-sensitive (e.g. food or postal) scale, and see if the "extended" one is double the mass. It should be if it has double the capacity (and thus reactants) in it! If not, well, you have a big case in which is a small battery...

I would be quite surprised if AccuBattery is wrong, by the way.... since they are simply doing that math (integrating charge rate in milliamps, reported voltage and time.) It's one of the reasons I like the app; it's proved quite accurate in my experience (within the realm of what you can reasonably expect without high-dollar instrumentation, which means +/- 15-20%ish.)

 

[Mooncatt]

Well I set mine up for return and will start looking at other options. The main reason I got this one was because it was a commonly mentioned brand, but it's certainly not at the advertised capacity.

 

[tickerguy]

I have a charger/discharger/cycler that plugs into my laptop and can run programmed cycles with very-accurate power measurement to go along with it. It's an extremely useful tool as it can be programmed to work with LA, NiCD, NiMH and Li chemistry batteries, either singly or in series combinations up to 20V or thereabouts (depending on chemistry.)

It will definitively measure the capacity of a given cell or given pack; you set it up for a given number of cells and their cut-off voltage, along with the desired discharge current, and let it rip; it produces a nice graph for you along with the EXACT millamp-hours (or amp-hours) that are required to draw the battery from its starting charge state (which it can charge to initially) until it reaches the cut-off. There's really no arguing with the results you get from it......

For just the discharge and capacity measurement side I also have a CBA, which is a West Mountain Radio device that is also very useful. I bought that a LONG time ago when I had a need to be able to run "burn tests" on high-capacity packs in situations where having a dead pack show up unexpectedly could kill you (e.g. cave-diving.)

I've found that AccuBattery is pretty close compared against what amounts to a near-lab-quality setup. It's not exact but then again the measurement tolerance requirements on a cellphone's internal circuitry are nowhere near as tight -- I wouldn't be surprised if the tolerance stack in the components within the charging system in the phone were only good to 10% accuracy, where something intended for precision charging and capacity management (really important if you're going to fast-charge lithium cells for things like RC planes at 1C and beyond and not have them catch on fire) needs to be trimmed for MUCH better tolerance than that -- maybe 1 or 2%.

 

[Mike Dee]

Well I set mine up for return and will start looking at other options. The main reason I got this one was because it was a commonly mentioned brand, but it's certainly not at the advertised capacity.

I have one and it's works great....just don't use the V20 that much

 

[Mooncatt]

I have one and it's works great....just don't use the V20 that much

Did you use a battery monitor app to check the actual capacity? The Perfine worked great for a stock capacity battery, but that's not what it's rated as. If yours checked out to be around 6,400mAh, I may consider getting a second one. I don't want to, but it's the only one in that capacity range with a flat back cover. All the others in that size have that obnoxious battery bump that drops off at the top of the phone, or is overkill in the capacity for me.

 

[Mike Dee]

Did you use a battery monitor app to check the actual capacity? The Perfine worked great for a stock capacity battery, but that's not what it's rated as. If yours checked out to be around 6,400mAh, I may consider getting a second one. I don't want to, but it's the only one in that capacity range with a flat back cover. All the others in that size have that obnoxious battery bump that drops off at the top of the phone, or is overkill in the capacity for me.

I got at least double my usage out of it