At least 2 uA quiescent draw are not so bad, I think Jay_Diddy_B's batteriser prototypes was about 20-30uA.
Don't know how to measure the switching frequency
...............
Who wants the two sleeves next? One will be shipped with the construction with the battery holder, for easy measuring. Would be cool if someone with ESD/EMV equipment could take a look at it, or verify the efficiency results with a non-bricked eload, or test the current limiter.
With 100 ohm load:
So far, the efficiency is about what I expected, but that sawtooth output is awful. It's hard to believe that isn't going cause issues.
So Frank has entered the first test in the spreadsheet (the toy train):
https://docs.google.com/spreadsheets/d/18K9c2YAT0d0QABGYGpzItbvDcgfAQCRUtloEzzfXADU/
And it was nothing short of a horrible result. -53% (minus!) Batteriser run time with a new battery, and a paltry 3.1% extra run time form the "flat" battery. Not 30%, not 300%, 3%.
It's a bloody awful result and I'd not expected it to be anywhere near that bad but can we be sure the original cell wasn't faulty* from the packet or was it repeated with other cells?
I guess the "dead" battery was allowed to recover for about one hour before test 3. One more interesting test as others have already mentioned is to measure a "dead" battery's extra time without the sleeve and after one hour recovery.
It's a bloody awful result and I'd not expected it to be anywhere near that bad but can we be sure the original cell wasn't faulty* from the packet or was it repeated with other cells?You are right, I should have measured the voltage. But the speed of the train was as fast as with the other cell, at least in the beginning, and the 4 minute result is not affected, because this was done with the other battery which was used in the first test.
Time confirmed, 61 minutes this time.
Anyone care to guess why the result is so bad? Simply looking at the efficiency does not explain it.
Frank, did you measure the current consumption of the train? Maybe I missed it...
Anyone care to guess why the result is so bad? Simply looking at the efficiency does not explain it.
Frank, did you measure the current consumption of the train? Maybe I missed it...
Current is about 250 mA at 1.5 V and 210 mA at 1 V.
Right, I guess it might be longer, too. But doesn't matter much, the interesting result is that the advantage is 3% instead of 300%.
I’ve seen some tests of AA batteries where the capacity variation in a 10 cell pack could be as much as 70% difference between the best and the worst cell from the same package. But this was the extreme case in the 9 brand test, other brands varied about 3-20%, so still something that really should be taken into consideration.
What are the capacity tolerances on a typical battery anyway? are they ever specified. I believe output voltage and internal resistance are monitored at manufacturing, but how about the capacity the battery can deliver when its energy is drawn over hours/days/months or even years.
Though I’m not saying this explains the test results we seen so far.
Anyone care to guess why the result is so bad? Simply looking at the efficiency does not explain it.
Frank, did you measure the current consumption of the train? Maybe I missed it...
Anyone care to guess why the result is so bad? Simply looking at the efficiency does not explain it.
Current is about 250 mA at 1.5 V and 210 mA at 1 V.
The MP3 player test is done. I used the method Dave described, just filming it, no measuring, to actually see when it turns off (looks like there was no low battery warning, maybe voltage jumped a bit). With sleeve a fresh battery worked 17.9% less long than without the sleeve and the additional time after using the sleeve on the dead battery from the first test with the MP3 player (which had a few days to recover) was 13.4 %.
Right, I guess it might be longer, too. But doesn't matter much, the interesting result is that the advantage is 3% instead of 300%.I understand your argument. I am just curious whether that 3% extra turns out to be 0% in real term.
I think your test results should be indicative for all direct battery powered motorized devices and "toys", including the monkey ...
The other device types of interest are those with built-in DC-DC convertors and those with pulsed power consumption. The interest is mainly on checking all different predictions made throughout the 300+ pages.