They have done a DinoDirect Increased the price for the WP2 to $20.99 and given a 25% discount which takes it down to $15.75.
I'm struggling to find a proper circuit to make a li ion solar charger with a 5V panel 1.25W...this one look perfect because has the battery host and the regulation perhaps would be changed to 200/280 ma which is the current provided for the panel.
Probably is based in one integrated circuit with a few components, I wonder if use the MCP73831 ( available at around 10 shipping included) that would be great since changing the program resistor is the only task to get what I want.
Some vendor has it at 7 dls...any feedback of this people ?
http://www.qualitychinagoods.com/xtar-charger-14650176701865018700-battery-p-1785.html
I have the MP1 now and so far it works great. One thing I noticed is that mine will charge my 14500 batteries even when they are above 4 volts. It tops out always at 4.17v when it goes green. According to the chinglish on the package it reads like it wont charge a battery unless it is below 4 volts but mine doesnt work like that.
You can trick it to charge a cell still above 4.00V to top itself. Replug the usb cable when the cell is still inserted. ;)
Thats what I did. Who would want to leave a battery on it until it discharged down all the way to 4 volts anyway? Thanks for reviewing this charger Budgeteer, it fits my needs perfectly. I like I can charge in my car so easily using my stereos usb. Plus it is so small.
Youre welcome. I'm just courious why is still so unpopular among others. Its really nice and inexpensive.
I scavenged the net for 2+ months for a decent li-ion charger... I was suspicious at first but i'm glad i did order a few (cheaper). Without it i would probably not use Li-ion's much. The "DX oem charger" is truly a TrustitwilburnyourhousedownFoy product...
Saved me to buy the way more expensive pila if i decided to eventually get one.
I saw a review of it on CPF that seem to knock it because it didnt maintain the same charge current through the charge, but does the battery really care? I like that my battery doesnt even get warm charging as that has got to be a good thing.
The way it's supposed to be done is constant current till the voltage hits 4.2V then hold the voltage there till the charge current drops to about a tenth of the original value. The constant voltage part usually takes a lot longer than the constant current (bulk charging) part.
Okay that makes sense. I didnt pay too much attention to the graph they had posted. I checked charging voltage on mine with the first battery I put in there and it was 4.2V so sounds like its doing what it is suppose to do. All 4 of my batteries have come off of it at exactly 4.17V everytime. It does take awhile to charge though, but thats fine with me. It just feels like a quality product and for only $6.50 its tough to beat.
http://flashlightreviews.ca/WP2-MP1.htm Here’s the review of the MP1 and WP2. It wasnt on CPF after all. Scroll down and you can see the chart of the different chargers. It is referencing current to time in the chart, showing the pile and WP2 maintaining a constant current. I guess the charger can maintain the same current input while keeping the voltage the same? I dont really understand that. It seems the current would naturally drop to maintain the same voltage which is what it looks like the MP1 is doing.
Woops, the full review is on CPF, sorry.
Li-ion batteries should never get warm to the touch while charging, if they do there is something rather wrong.
Why? The one I got has an open voltage of 4.20V so the cells will never go above that.
Look at the internals. Also does not do CC/CV. Emit sounds when batteries below 3.1V and smells funny. A few of these simptoms can also be read at dx. If it was not for the Mp1 with which i feel reasonably safe i doubt i went as far as i did in Li-ion. Surely would not even bother to try selling one to someone. I only sell flashlights along with decent batteries and charger. Charger is always Mp1. No complaints so far. If they were 20usd each that might change but since they are very cheap i'm happy with them so far.
CC/CV only affects speed, not safety (as long as you don't exceed the maximum voltage or current), and in this case the MP1 doesn't do CC/CV either and is much slower than the OEM charger. My unit doesn't smell or make sounds (But then I don't drain my cells below 3.1v either).
The problem with slow chargers such as the MP1 is that it takes too long time for someone to supervise the charging (which you always should when charging loose chinese li-ion cells).
I've considered getting the XTAR WP2, but if it's slower than my current charger then I won't really gain anything.
I doub't you could create a fire hazard with these chargers unless you have unprotected cells that are drained too low (which is unrelated to the charger). Now, if you talk hobby chargers instead then you have very effective incendiary devices...
Well, in the review on CPF i gathered that the CC/CV isn't perfect but it's there. I have to reread it one day. I also do not use cheap cells. I've left the charger unattended and even overnight several times. While i'm not proud of it and would not reccomend this at all, i was pretty surprised when i measured the battery with my multimeter and went away smiling (even the sony unprotected i cannibalized a laptop battery for).
The ticket for me was the well built and reasonably priced charger. I got it and very happy ever since. The fact alone that can be used on a USB host being a pc technician was a bonus. I even managed to charge a battery while in car. :)
I will probably use the DX charger as a battery holder for testing purposes as i'm hesitant even to gift it.
The ones DX sells quickly became very unattractive and my DX charger sits in a drawer to remind me why i get these instead. But hey... this is my call... feel free to do what you think is right for you.
I spent much time last year reading DX forums for a best charger to get which only left a bitter taste while digging into it. If i did not went the guinea pig route for the XTAR Mp1 / Wp2 i would probably have bought a pila charger instead.
Is the MP1 able to charge 26650’s?
I think you'd have to slip a conductive shim between the + end and the contact on the charger to get it to work... (I don't have any 26650s, but I've dropped a 25mm holesaw into the charger, and eyeballing it, it doesn't seem like it'll line up well enough to make good contact.)
I've read rom HK reviews it is possible but just barely.
Qualitychinagoods still the cheapest place to get these?