I found a few of my old travel chargers that light up the Charge LED when connected to the UPS. I'm using this to charge both of them right now - that seem reasonable? I'm using the two Quick Charge ports on it, as they had the highest output readings.
Ha, I purchased the same cells. I'm testing them now, and from owning hundreds of lithium cells over the last 8 years, these so far, don't seem so great. I still need to run them through a few charge/discharge cycles to "exercise" the guts.
I don't own many of the LiPO4, mostly LiIon cells, but to me these LiPO4 cells were stored/shipped at too high of a voltage. I received the cells at 3.35 volts and I know storing LiIon cells at too high of a charge is detrimental, and probably not good for LiPO4 also.
And I ASSume Digikey doesn't sell a large volume of these, so who knows if they are fresh.
I'll report back on capacity and internal resistance once my tests are complete...
Just looking around at the big name LiFeP04 OEM's, PowerSonic seems to be very well regarded (been in the battery industry since the 70's) and might be worth a look if the cheaper batteries dont work out.
It's what I do. Ask my mother, wife, former GFs, family and friends and co-workers.
But...unfortunately one unit doesn't seem to like me very much. haven't had time to do a bunch of testing, but:
When I came out this AM, unit 1 charging ligth was out, as expected after charging all night. Unit 2 was still reporting charging.
When I unplugged both of the units, unit 1 showed power loss LED, unit 2 didn't show any change.
I swapped batteries between the units and unit 1 continued to behave normally (batteries showed fully charged, power failure LED on when unplugged) and unit 2 behaved as before, showing charging when plugged in and no power failure light when unplugged.
I checked power output on the two units on a simple meter I have, and then switched batteries and didn't find any difference resulting from battery swap, unit 2 consistently showed the lower output, and the power failure light isn't coming on.
One question in general is whether the output level on unit 1 is as expected? Just want to confirm what "normal" is.
Anything I could have done to cause the issues w/unit 2? I know you tested these before shipping. had to bend out the battery tabs to make them have good contact w/my batteries, so while I was bending and testing the fit I could easily have put one or more of the batteries in the wrong way. Could that have caused behavior like this? Let me know what you'd like me to try/report.
I know it's not DIY, but here is an option that can stay charged with a separate wall wort and provide power when charging. It will also provide about 14 hrs of backup (not tested by me). I once was going to go the Konnected route at another house, but changed my mind.
Honestly, What that device provides is pretty much why most people here are excited about this DIY item that @dJOS has put together for us. I don't now if that was known about, we would all be getting so excited for this DIY item.
Great find.
I wonder if it can do 5v and 12V at the same time.
No, not as designed. The base IC TLC4040 from TI is designed specifically for 5V applications. IMHO this device is way better than most Lixxx based UPS in that it will not charge the batteries to the max, resulting in much longer battery life and minimal loss of run time.
For the other folks in the states that recieved it. Did you get any indication UPS was delivering it before they showed up. Mine is still just showing it arrived in US and that is it.
That is odd - at the most basic level, it should show a power failure as soon as batteries with more than 20% charge are installed. Are your batteries "button tops" or "flat tops"?
I'm wondering if the holder isn't making good contact with the batteries. I used button tops that really push out the spring terminals. It may be worth trying to extend them away from the case so they apply more pressure to the battery terminals.
~5v output is expected - 4.99v is withing spec.
Putting the batteries in the wrong way won't hurt anything - I've tested this several times (intentionally, of course )
Based on observations from @Rxich, I'm wondering if these batteries are just crap - I can't even find them on DigiKey anymore. Can you see if you can find a supplier selling these batteries from Power-Sonic? They are very close in spec to what I tested all the units with.
I purchased "LithiumWerks" batteries. They came in a plastic two battery case, looked fresh. I measured both and there are 3.2187 BOTH OF THEM !
I tried them in a 18650 flashlight and both seemed to work fine. Se well see how they work with the UPS when it arrives. But as of this moment I'm happy with them.
The tracking number does work with USPS. I loaded the USPS app on my phone and was able to get a bit more data. Looks like it has left Cali and is on its way across country. Sais it left the USPS facility in Carson, CA. You may be able to get a little bit more detail that way if you want.
