david.allie
Newly Enlightened
I have a new XTAR Dragon VP4 Plus charger and began recording data before-and-after each charge/refresh/test cycle. I had bought 8 Odec C-cells through Amazon and was eager to see the results.
To explain what's in each column:
col 1: IGNORE, simply a # assigned to a battery
2: manufacturer
3: cell size
4: claimed mAh rating
5: date of last charge/refresh/test
6: actual mAh rating
7: charge/refresh/test (C/R/T)
8: charging rate
9: notes
004 odec C 5000 03.05.2018 4193 T 0.5 # generic flourescent, emergency light
005 odec C 5000 03.05.2018 3786 T 0.5 # generic flourescent, emergency light
005 odec C 5000 03.08.2018 3704 T 0.5 # generic flourescent, emergency light # pre-charge voltage = 1.39 IR = 038, 81% # this is just 3 days after last Tcharge # post-charge voltage = 1.45 IR = 017
006 odec C 5000 03.05.2018 4347 T 0.5 # generic flourescent, emergency light
007 odec C 5000 03.05.2018 3902 T 0.5 # generic flourescent, emergency light
008 odec C 5000 03.06.2018 3753 T 0.5 # generic flourescent, emergency light
008 odec C 5000 03.08.2018 3949 T 0.5 # generic flourescent, emergency light # pre-charge voltage = 1.41 IR = 010, 89% # this is just 3 days after last Tcharge # post-charge voltage = 1.48 IR = 015
009 odec C 5000 03.06.2018 3980 T 0.5 # generic flourescent, emergency light
010 odec C 5000 03.06.2018 4545 T 0.5 # generic flourescent, emergency light
011 odec C 5000 03.06.2018 4280 T 0.5 # generic flourescent, emergency light
These Odec C-cells claim to have a 5000 mAh rating. You'll notice that the actual ratings are substantially lower. The mean-average actual is 4043 mAh, which is almost 20% lower than claimed.
Furthermore, I noted that cells #005 and #008 had the lowest initial scores, so I retested them. Cell #005 did worse, an approximate 2% difference. Cell #008 did better, an approximate 5% difference.
I suspect my buying the Odec C-cells is an example of "caveat emptor"/"buyer beware". The Odec C-cells were quite low cost, so I suspect this was just a case of "you get what you pay for".
SLIGHTLY OFF-TOPIC: As I recently bought an Acebeam EC-50 generation 3 flashlight that came with an Acebeam 26650 cell. While I know its not fair to compare a C-cell to a 26650, they both are rated at 5000 mAh and the results from the first Acebeam battery were quite impressive:
001 acebeam 26650 5000 03.03.2018 5361 T 0.5 # acebeam ec50 gen 3 flashlight
I was so impressed, that I ordered 2 more Acebeam 26650 batteries. Similarly, the Panasonic eneloop/pro AA/AAA batteries I bought also gave me actual mAh ratings that significantly exceeded their claimed rating.
ANYWAYS, BACK TO THESE ODEC C-CELLS: I'm planning on buying 6-8 Powerex C-cells, which are substantially more expensive. Once I've bought and tested some Powerex batteries, I'll report back.
IN SUMMARY: I will avoid buying Odec batteries in the future. While they are less expensive, that cost savings amounts to an approximate 20% reduction in actual mAh rating. These C-cells will be used almost exclusively in an older flourescent-tube emergency light and given that the first time I used these C-cells, this light stayed on for approximately 8 hours... so theoretically a set of actual 5000-mAh batteries should amount to about 2 more hours of light. TWO MORE hours of basic light can mean a lot when you're depending on a lantern during an emergency or blackout.
POSTSCRIPT 1: I gave these batteries two stars (out of five stars). Three stars would've been "average, I might buy more". Two stars for me is "average, but I won't buy more".
POSTSCRIPT 2: I recognize that an even-better charger like the SkyRC MC3000 might do better at packing in a bit more power into these C-cells, it's more expensive than my XTAR Dragon VP4 Plus... but given that this XTAR charger is probably more expensive than the average consumer wants to spend, I think I can say the the raw data I collected (and decision made after) is objective, fair, repeatable and honest.
To explain what's in each column:
col 1: IGNORE, simply a # assigned to a battery
2: manufacturer
3: cell size
4: claimed mAh rating
5: date of last charge/refresh/test
6: actual mAh rating
7: charge/refresh/test (C/R/T)
8: charging rate
9: notes
004 odec C 5000 03.05.2018 4193 T 0.5 # generic flourescent, emergency light
005 odec C 5000 03.05.2018 3786 T 0.5 # generic flourescent, emergency light
005 odec C 5000 03.08.2018 3704 T 0.5 # generic flourescent, emergency light # pre-charge voltage = 1.39 IR = 038, 81% # this is just 3 days after last Tcharge # post-charge voltage = 1.45 IR = 017
006 odec C 5000 03.05.2018 4347 T 0.5 # generic flourescent, emergency light
007 odec C 5000 03.05.2018 3902 T 0.5 # generic flourescent, emergency light
008 odec C 5000 03.06.2018 3753 T 0.5 # generic flourescent, emergency light
008 odec C 5000 03.08.2018 3949 T 0.5 # generic flourescent, emergency light # pre-charge voltage = 1.41 IR = 010, 89% # this is just 3 days after last Tcharge # post-charge voltage = 1.48 IR = 015
009 odec C 5000 03.06.2018 3980 T 0.5 # generic flourescent, emergency light
010 odec C 5000 03.06.2018 4545 T 0.5 # generic flourescent, emergency light
011 odec C 5000 03.06.2018 4280 T 0.5 # generic flourescent, emergency light
These Odec C-cells claim to have a 5000 mAh rating. You'll notice that the actual ratings are substantially lower. The mean-average actual is 4043 mAh, which is almost 20% lower than claimed.
Furthermore, I noted that cells #005 and #008 had the lowest initial scores, so I retested them. Cell #005 did worse, an approximate 2% difference. Cell #008 did better, an approximate 5% difference.
I suspect my buying the Odec C-cells is an example of "caveat emptor"/"buyer beware". The Odec C-cells were quite low cost, so I suspect this was just a case of "you get what you pay for".
SLIGHTLY OFF-TOPIC: As I recently bought an Acebeam EC-50 generation 3 flashlight that came with an Acebeam 26650 cell. While I know its not fair to compare a C-cell to a 26650, they both are rated at 5000 mAh and the results from the first Acebeam battery were quite impressive:
001 acebeam 26650 5000 03.03.2018 5361 T 0.5 # acebeam ec50 gen 3 flashlight
I was so impressed, that I ordered 2 more Acebeam 26650 batteries. Similarly, the Panasonic eneloop/pro AA/AAA batteries I bought also gave me actual mAh ratings that significantly exceeded their claimed rating.
ANYWAYS, BACK TO THESE ODEC C-CELLS: I'm planning on buying 6-8 Powerex C-cells, which are substantially more expensive. Once I've bought and tested some Powerex batteries, I'll report back.
IN SUMMARY: I will avoid buying Odec batteries in the future. While they are less expensive, that cost savings amounts to an approximate 20% reduction in actual mAh rating. These C-cells will be used almost exclusively in an older flourescent-tube emergency light and given that the first time I used these C-cells, this light stayed on for approximately 8 hours... so theoretically a set of actual 5000-mAh batteries should amount to about 2 more hours of light. TWO MORE hours of basic light can mean a lot when you're depending on a lantern during an emergency or blackout.
POSTSCRIPT 1: I gave these batteries two stars (out of five stars). Three stars would've been "average, I might buy more". Two stars for me is "average, but I won't buy more".
POSTSCRIPT 2: I recognize that an even-better charger like the SkyRC MC3000 might do better at packing in a bit more power into these C-cells, it's more expensive than my XTAR Dragon VP4 Plus... but given that this XTAR charger is probably more expensive than the average consumer wants to spend, I think I can say the the raw data I collected (and decision made after) is objective, fair, repeatable and honest.
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