Is there any downside to leaving my clip plugged into an AC charger while I listen to it during the day? Would this extend my battery life, or shorten it from overcharging?
This will not harm your battery. From what I’ve read, lithium-polymer batteries are built with circuitry that senses when the battery is fully charged and shuts off any further charging at that point.
I can only find reference to this for Li-Ion, not LiPo, but they are basically the same chemistry so I would expect them to behave somewhat similarly: The Li-Ion battery should be stored at about 40% fully charged to prolong it’s life. One site I found stated that the capacity of Li-Ion stored at 100% charge decreased to 80% after one year and those stored at 40% charge only decreased to 96% after one year. (Battery Storage FAQ, battery manufacturer's recommendations for storing batteries, storing lead acid, sealed lead acid, NiCad, NiMH and lithium ion batteries). LiPo may do better than this.
In terms of playtime, this means a player that will run about 16 hrs now would only run about 13 hrs a year from now if kept charged all the time. (yes, I rounded those nums).
So… if you leave it plugged into a charger all the time, you are essentially storing it at full charge and I would expect to see it lose more capacity after a year than one that had been cycled (discharged, charged…).
What I am doing is letting it discharge, then recharge it, even though I can run it a really really long time off an external battery pack I made. When I take off somewhere and the clip power is low, I plug it into my external pack and drop that into my pocket, still powering (and charging) the clip, and run it until I notice it is charged up, then disconnect the external pack to run off the clips internal battery. Only time will tell if I m doing the right thing, though. It looks like this:
Robert
Nice set-up, Robert. Are those 4 AA’s, or 8? I can’t tell from the picture if there’s a second layer. I’m guessing 4 should suffice? Rechargable NiMH batteries would work as well, right? Thanks for the picture.
It’s just 4 AA NiMH batts in a holder from Radio Shack. I cut a USB cable and soldered it together. Pretty simple, actually.
DON’T USE ALKALINES - The voltage is too high.
If I did it again, I’d find a more flexible piece of cable to use.
Robert
Nice mod robert… Maybe you could sell em 
lol
The one pictured would cost around $12. $1.79 for the battery holder at radio shack, and around $10 for the batteries at wal-mart (and with 2 boys with lots of battery powered toys, not to mention cameras and flashes, etc., I have bunches of those batteries so I didn’t really buy them for this, I just grabbed some out of our stash, making my real cost only $1.79 + tax, probably cost me more in gas to run out and buy the thing). The cable was just one I had laying around. The only other thing is the three pieces of heat shrink tubing, which not everyone has laying around. Heat shrink is much better than tape for this. Looks like you can buy that at radio shack for ~$3.00, although I buy 3 ft. pieces in bulk, so the amount I used was just pennies… And, of course, a soldering iron and solder.
Robert
I use this one http://www.mobiledriven.com/usbbaexaaba.html to power/recharge a variety of devices (Clip, cell phone, GPS, etc). I bought it at Walmart for $8.97.
Message Edited by dusky on 01-24-2008 11:53 AM
