I use all of my lights, a lot, and thought I was having my first failure the other day, in a Fenix LD25. I noticed it was getting a lot warmer in use than normal, and I was having to charge a lot more into the batteries when I changed them each day compared to what I used to for the same amount of runtime use. It was happening with all 4 pairs of cells I cycle through this light (and they are also used in a Quark Turbo AA2). The LD25 and Quark get exactly the same amount of use each day as bike lights, and it used to be that the amount I charged into the 2 pairs of cells each day were within about 200mAh of each other. Then I noticed the difference was more like about 500-600mAh. The cells are Imedion 2400 with 120-140 cycles on them doing this duty, and they get beaten about a bit because they're attached to a bike. They've taken a few knocks because they're not quite as long as they used to be...
Give or take I usually need to charge about 50% back into them each day. Now I have to charge an extra 500mAh or so into whichever pair was in the LD25 vs a relatively normal about for the Quark.
A runtime test on the LD25 at home with the "bike" batteries only gave me about 45 minutes runtime in high, vs at least 1:35 if not longer normally. But a Refresh&analyse (1000mA/400mA) on the c9000 said the cell's capacity was about 97% of their original capacity. The 1A pulsed discharge on the C9000 is less than the 2 torches though, I guess. Discharging on the C9000 didn't show a particularly reduced voltage (from high resistance). So I thought it was the torch failing but on a whim tried some less abused NiMH's and voilà, was back to the expected runtime.
This is all very curious because
a) The same cells get used in the Quark Turbo and its doesn't seem to be exhibiting the same behaviour even though it has a lower runtime (hence higher current draw) in turbo mode compared to an LD25
b) The cells don't show any of the normal signs of a poor battery on the C9000 (either capacity of <85% or high internal resistance, or voltage drop under load) ... yet
So I dunno what's going on. Any ideas? Something in the way the circuits on the 2 different lights work that makes the LD25 more susceptible to batteries that could be on their way out? eg. a higher current pulsed drain of some sort? A fault in the LD25? I've still got a month or so of warranty left.
Happy to hear some theories :thinking:
Give or take I usually need to charge about 50% back into them each day. Now I have to charge an extra 500mAh or so into whichever pair was in the LD25 vs a relatively normal about for the Quark.
A runtime test on the LD25 at home with the "bike" batteries only gave me about 45 minutes runtime in high, vs at least 1:35 if not longer normally. But a Refresh&analyse (1000mA/400mA) on the c9000 said the cell's capacity was about 97% of their original capacity. The 1A pulsed discharge on the C9000 is less than the 2 torches though, I guess. Discharging on the C9000 didn't show a particularly reduced voltage (from high resistance). So I thought it was the torch failing but on a whim tried some less abused NiMH's and voilà, was back to the expected runtime.
This is all very curious because
a) The same cells get used in the Quark Turbo and its doesn't seem to be exhibiting the same behaviour even though it has a lower runtime (hence higher current draw) in turbo mode compared to an LD25
b) The cells don't show any of the normal signs of a poor battery on the C9000 (either capacity of <85% or high internal resistance, or voltage drop under load) ... yet
So I dunno what's going on. Any ideas? Something in the way the circuits on the 2 different lights work that makes the LD25 more susceptible to batteries that could be on their way out? eg. a higher current pulsed drain of some sort? A fault in the LD25? I've still got a month or so of warranty left.
Happy to hear some theories :thinking: