4.17v is great in my opinion. I did some tests with my hobby charger and the difference between 4.2 and 4.17 was only about 3% if I recall correctly. From what I understand the batteries will last longer and be happier when charged to < 4.2.
Canât help you with the smell, it may just be burning off some residue from the manufacturing process, how old is the charger?
As for only charging to 4.17 volts, itâs GREAT for the batteries. As I understand it, the closer you get to max capacity per charge, the shorter the life of the battery. The flip side of this is that the less MAHâs stuffed into the batteries, the sooner they need to be charged. It would be an interesting long term experiment to see where those two graphs intersect. Number of lifetime charges vs hours of useful output vs end voltage.
hmmm, lets see, Iâll need a sponsor, a fleet of batteries, a fleet of chargers with precisely controllable end voltage, a couple dozen identical flashlights⊠Should probably have them all in integrating spheres to watch the light outputâŠ
I think I might have a related problem. Iâve bought a new Xtar VC4 and went on to charge 1 AA (I donât remember the brand) that usually holds 1600 mAh, as tested with my other charger, the Opus BT-C3400.
The thing here is that the charger keep charging the battery until about 4600 mAh were show in the display⊠I was afraid it was going to blow away! The voltage was at ~1.45 but it kept charging and charging (the battery was very hot).
I left the charger working in a safe spot, went to sleep and found out the next day that it stopped around 4600 mAh @ 1.5 v. Should I worry about it? How could it be possible that it putted that much mAh into the battery and it didnât blow up?
Please let me know what you think; thanks in advance.
BTW, it was a battery that started with the â0v revival functionâ, i.e., other smart chargers (as the Opus) wouldnât even recognize it because of the low voltage that it had, so I used this function from the Xtar to charge it. I donât know if this would have anything to do with it.
if i were in xtars shoes i would want to know RIGHT FN NOW! if i had a bad batch of chargers that would replicate the samsung note 7 fiasco so i could recall them,pull off the shelves and get them all back.
but thats just me.
on the good side you have to really overcharge a high quality modern cell to get a nasty outcome.like 12v
iirc thats one of the ul tests.
with whateverfire grade cells all bets are off.
Same like float-charging Pb-acid batteries. Theyâll soak up (depending on their size) a certain amount of current without increasing their voltage, so you can hit âem straight from a 24V bell transformer (and diode, etc.) with only an appropriate-value series resistor, and theyâll safely float away for their full service life without a hitch.
Thatâs why I like those cheapo 2buk chargers FT sells, because theyâre so low a charging current youâd really have to leave them in for days on-end to hurt the cells.
A fast-charger, of course, needs to be WAY more critical in its source voltage.
One suggestion, or at least something on my âwish listâ, is to have an option to charge a cell to only 90% capacity, for longer life at the expense of runtime.
Charging to only 4.1V (or 4.0V), say, would also leave more âheadroomâ in case of overcharge.
Before all dogpiling on XTAR , letâs wait to hear back what their customer-service says.
I got a WK50 with a bit of a wonky switch (only intermittent problems), contacted the vendor to see if they had just a replacement switch to send, vs snailmailing everything backânâforth, and was told to keep the light, theyâd send me another (itâs on the way!), and even sent instructions with pix as to how to take apart the tailcap and play with it myself to have 2 working lights. I was sufficiently wowed.
Absolutely, itâs in XTARâs best interests to get back the charger and find out what went wrong, even if they have to eat the cost of return postage. A few bad incidents of Li cells going supernova would make XTAR chargers the equivalent of Galaxy phones. Forget recalls (shady sellers would keep selling them anyway). What theyâd lose in terms of sales just from BLFers would be probably hundreds of times the cost of the return postage.
I kinda get the feeling that one of their distributors in Canada would realise this and offer to cover return postage.
With a hobby charger like the I charger not sure the model and the clone versions of it. You can set it to cut off at a exact voltage like that. And during the discharge test you can set the exact cut off voltage you want to terminate at
Idk if this helps but I just received my xtar vc4 charger yesterday and straight out of the box before I even plugged it in it has that almost burnt like electronic smell so strong that it can smell it while laying in bed, sitting on my night stand right next to me. Itâs strong but isnt the exact smell from burnt electronics but its close. Alot of electronics when new have strong smell to them till them break in kinda heating off the smells with regular use. Alot of glues used in the transformer wrappings and certain materials used create an odd smell. Iâm an certified automotive technician and know what burnt electronics smell like and even though this is close it isnât and at least with mine everything is fine. So far mine seems to work as advertised. Hope this helps
Also all printed circuit boards have a like glazed coating on them to protect the current paths from arcing out on foreign objects which wold create shorts, this coating has a smell that may be associated with âburntâ or âbadâ electronics. After time once the coating fully cures the smell will dissapate. Sometimes âheatâ from normal usage will agitate the smell for a certian period of time
Take a poor quality battery, run it dead > it may end up even worse.
NiMh termination is MUCH harder than Li-on CC/CV. Missing termination, or early termination, can indicate a problem with the battery, the charger, or both with a kind of compatibility issue. In this case I would strongly suspect the battery, not the charger. The VC4 is one of the more reliable chargers Iâve had.
Iâve got a few NiMh that donât terminate properly. Generally they are old and abused, but not always. Iâve had it happen to new AAA Eneloops. I mark them, watch them, and if they continue to do so are trashed.