Alright, it looks like you guys have sold me on the Vapcell…
I just recently saw a relatively new (new to me) type of LITHIUM ION cell (Hixon brand).
They run at 1.5 volt in AA & AAA sizes? They’re not NiMh nor NiCd but true li-ion!
Will this charger automatically know to charge these li-ions for 1.5V instead of the ~4.2V that Li-ion typically get? Or, would I have to manually change some settings for these relatively new types of batteries? Or, would a dedicated Hixon charger be necessary?
I don’t think any of the current LiIon/NiMh chargers can charge this type of cell. The dedicated charger would be required.
Read the Xtar thread, there are some upsides to this kind of cell. But they are not ideal for some applications.
They do have a LiIon cell inside that is the typical 3.6V nominal but charges to 4.2 as is typical. They then use a (lossy) buck converter to get the 1.5 V out.
There are also a few reviews of this 1.5V LiIon with buck converter type cells on BLF as well as other places if you do a search. A couple of these are linked in the thread above.
They are fairly recent, but have been around for… maybe a couple of years.
These cells have mostly an USB-C-connector to load it.
Some brands like Xtar (maybe also Hixon) have those cells without USB-C, with them you need a special charger which works (only) for these cells.
I think Vapcell have planned to bring us a charger which can also do LiIon and NiMH, but it´s not yet released.
The 1,5V LiIon are not unproblematic because of the voltage converter which uses high frequencies to convert the typical LiIon-voltage to 1,5V. This could cause problems/failures with some devices, e.g. thermometers with radio-receivers (don´t if this is exactly the wording)
Well, I have it.
I use mostly for capacity test as a discharger for AA-cells because it don´t decrease the seected discharge rate like my NC2200.
The display is still the worst I ever seen. One value for one cell, only switching between cells, not between values; you have to wait if you want to see the actual voltage because it´s the 4th value of a cell.
I am not a fan of the display function either. But you can press the slot button to move around the slots in rotation. That being said, I have and use three of them. They are my go to chargers for NiMh charging, testing, and a true IEC break-in cycle. They also have a real nice top off function which will get another 5% or so into the cells. If you have the patience to let the cells sit in the charger for an additional one to two hours.
But they don’t charge anything but NiMh (or NiCad). So they are not really applicable to this discussion. Great chargers though, for what they do.
Went to order the Vapcell from illumn, but cancelled the order after seeing that they wanted nearly as much to ship the charger as the sale price they’re asking for it.
I think there’s some (apparent) confusion here regarding this. Some are assuming you’re referring to an unprotected cell which has been discharged to at or near zero volts, and in that case, they cannot be safely recharged. Opinions / sources vary, but that lower limit is probably in the 1-2 V range. Attempting to do so can be dangerous and is NOT advisable.
If you’re referring to protected Li-ion cells which have been discharged below the low voltage protection limit (often ~2.5-3.0 V), they will measure ZERO volts, but the protection circuit can be safely reset by applying an external voltage to them briefly. My XTAR VP2s do it, and I use that function when I accidentally over-discharge a protected cell beyond the protection limit (and as a result they are at ZERO volts). This is an advertised feature of most Xtar chargers. I’m told that this can also be accomplished by briefly connecting a charged cell in parallel with the ‘tripped’ cell, and many do it that way if their charger doesn’t have that feature / function. Some chargers do, and some don’t. I think you were referring to the latter case involving a protected cell, and yes, that’s a valid feature you can look for as you shop.
So, there are 2 different situations involving ‘overdischarged’ cells, and they are apples and oranges different.
I can´t remember on which Homepage I read something about 0V-recovery but there were no detailed explanation, nothing to read from protected cells. In the Vapcell manual (i have only the german version) it´s also mentioned without further explanation.
But IIRC the Vapcell shows “Err” with a over discharged NiMH while my Xtars start immediately charging if the cell have around 0,1V
1.5V Li-ions should absolutely NOT be charged in a normal NiMH or Li-ion charger. They need to be charged in either the manufacturers dedicated charger (which they would generally state pretty clearly on their website), or if available via integrated USB port.
It is not concerning the Hixon cells you mention, but they do discuss charging as well as some of the benefits and liabilities of using this kind of cell. Bottom line is, @stephenk is absolutely correct. None of the chargers we have talked about, including the one you bought can be used with these cells.
I have liitokala lii-202 and 500 models.
My friend have lii-pd4 and lii-600 and I try it.
My lii-500 charge nimh to about 95% of full, I try it to discharge on opus 1 slot charger and see the result so it is solid charging.
Lii 600 have better charging and I see temperature raise on the end of charging which say that it have -dv/t termination
Thanky you for the answer 95% full would be OK for me
I think you mean-dv/dt ?
A temperature rise says that the NiMH is close to be full (as long you don´t charge with too high current) but doesn´t mean there´s a -dv/dt termination, it´s a dT/dt termination (dunno which charger use it?).
A -dv/dt means there is a very small voltage drop which tells the charger to stop. I think I have some chargers which use it but never see the drop on the displayed voltage.
I remember charger reviews that Silverfox did over on CPF. I liked them because he would compare the percentage of capacity achieved by different chargers. But I often wondered how he got the numbers.
So, may I ask, how do you measure the 95% full? What is your criteria for 100%. Is that the rated capacity or something else?
I suppose we could just do a discharge and see what the results are. But that is variable. At least I typically get variances of maybe plus or minus up to 3-5 percent when testing the same cell multiple times. Also, I hardly ever get capacity results that match the rated capacity. So that 100% is an elusive target.
I charge the same cell on lii-500 all 4 slots and write results when that cell discharge on opus bct100 and on opus 3100.
After that I charge and discharge same cell on that 2 opus chargers and compare the results.
I think that opus is very good charger for nimh.
For black eneloop 2500 mah I got result that lii-500 charge that battery to aproximatelly 95% of full capacity in comparation with results on opus chargers. For tronic 2500mah cells that result is 90%.
I try it many times and I can say that charging nimh with 1 amps on lii-500 is not good idea, because older cells with higher intenal resistance will overheats and best results is when charge with 300 and 500 ma.
Lii-500 work good with eneloops and varta 2100 cells.
So when I write 95% of full capacity It was comparation with capacity which opus charger pump in same battery.
When I try normal test on lii-500 I haven’t never get results which will be close to nominal capacity, concretely, I get about 2400 for eneloop pro and about 1780 for eneloop standard.
I think that lii-600 which I try is better charger than lii-500 for nimh.
All my conclusions is amateur but it can help me to see what to espect from this chargers and what are their limitations.
OK. Thank you for the explanation. So this is more comparing the chargers than actually understanding how full the cell is compared to its advertised capacity.
I get it.
95% full would be OK for me