Universal Li-Ion charger

Yes the Eco6 and Variable6S are the cheaper clones I mentioned which Hobbyking warn about in their AC6 page ("There are several chargers now entering the China market that look similar to the Accucel. These chargers are produced with cheaper FETs and are unfortunately much less accurate and very unsafe. There has been reports of the copied chargers over-charging packs and not balancing correctly") but are now selling anyway.

Some people say the calibration, heatsinking, components and general quality of the clones also tend to be more spotty then the AC6 although the reviews of the Eco6 are good so far (the Variable6S is too new to have reviews). I noticed the Eco6 and Variable6S are lighter which means you have more weight for shipping extra stuff if you're going with the 251-500g option. BTW in terms of the fan, I'm not sure how important it is for charging, I've read comments suggesting it's only really necessary for discharging (which isn't that surprising if the charger isn't super inefficient), some of the clones come without a fan and even with the AC6 a common complain is the fan is noisy and/or dies.

This is getting OT but one of the shortcomings for me with Hobbychargers is they are only one channel chargers (well there is one that appears to be 4 cheap hobby chargers in one box that is multi channel but even for many of the expensive ones they are usually just designed for high power for charging lots of matched batteries and lipo batteries at very high rates like hobby charging people do). So you should only charge 1 cell if you aren't sure how well matched they are or you know they aren't matched well at all. For li-ion you can use balanced or parallel charging and provided the cells aren't too different this works fine (I've read conflicting info about how well matched the cells should be but within 0.5V seems common for parallel charging, definitely one nearly completely charged and one nearly fully discharged is not recommended). In fact it would generally be better if you want to use both cells together like in a 2x18650 flashlight since you do obviously want to cells to be well matched (although from what I've read the cheap chargers like the AC6 don't give any indication if the cells aren't well balanced so you should still test them, you could of course use the hobby charger to do so). Some useful links http://www.candlepowerforums.com/vb/showthread.php?t=249066 http://www.candlepowerforums.com/vb/showthread.php?t=263961 http://www.candlepowerforums.com/vb/showthread.php?t=255467 although plenty of related discussions from a quick search (the RC forums would also be useful).

But because most hobby usage of NiMH and similar chemistries generally involves packs without any balancing option and the difference in the chemistries means parallel charging is a bad idea (http://www.candlepowerforums.com/vb/showthread.php?t=263514 http://www.candlepowerforums.com/vb/showthread.php?t=187120 http://www.candlepowerforums.com/vb/showpost.php?p=3443903&postcount=13), so you can only charge in series and if the cells aren't fairly well matched you should only charge 1 at a time (or whatever you have that are matched). This may not matter for some and you do get a decent 1 channel NiMH charger including with the ability to set the charge rate and do a discharge for conditioning but for me as one of the thoughts with a hobby charger was I also can use it as a general purpose NiMH charger it does make it somewhat limited (although you do get the ability to charge only 1 cell at a time or 3 matched cells or whatever, something a few NiMH chargers can't do since they are 2 cell 1 channel commonly x 2).

Another thing to be aware of is that hobby chargers aren't exactly plug and play (well some of the more expensive ones may be). Other then usually needing an external PSU and of course some sort of home made cradle or magnets or whatever if you want to charge loose batteries, you do need to be careful with the settings and not accidentally set them wrong. And also take care with how you plug in (and assemble any cradles) since you could kill the charger, or worse cause a fire or explosion if you set something or plug something in wrong. (There are a few reports of such problems, more so then with the cheap cradle chargers, the AC6 manual has various warnings about what you shouldn't do which I think are more then just CYA.)

There's a review of the Ultrafire WF-188 out now from old4570 http://www.candlepowerforums.com/vb/showthread.php?t=282815. The results are somewhat as I expected. It's basically similar to the refined WF-139 but with voltage and current/charge rate adjustment. In other words no CC/CV but it does terminate at about 4.2V sort of. I say sort of because it evidentally has a similar contact point flaw to the Shekor. Not to ruin anyone's research but I noticed from there that there's also an Xtar 6 cell charger http://www.cpfmarketplace.com/mp/showthread.php?t=231713 but it isn't exactly cheap.

Hi Nil,

Have decided against jumping in the deep end with a hobby charger.

My head tells me I should err on the side of caution and go for the Shekor as it seems to be one the safest both for cell health as well as charge termination.

But if I understand it the WF-188 without modding does the same slight undercharging, just a bit faster.

I'm interested to see how the reviewer gets on with charging 10440s.

Am I right in thinking that the charge current on the Xtar WP6 is not great for 10440s?

Thanks,

Gary

Yes 600mA would be considered too much, from what I read the true capacity of these tends to be under http://www.candlepowerforums.com/vb/showthread.php?t=236351 350mA so you're nearly 2C not good for li-co cells where 1C is generally the recommended maximum.

The WF-188 seems okay particularly if modded although even then it doesn't follow the CC/CV that the Shekor probably does if modded. In my case I've decided close to CC/CV is best (well ultimately it's what the battery manufacturers recommend) if I can do it cheaply and it seems the Shekor hopefully fits that bill (but I don't really care about anything other then the 18650). It's actually a pity the HXY are so questionable since for my case if they were CC/CV as they were at some stage they would be better since they'd be great for 18650.

Not all agree about CC/CV, e.g. old4570. The Shekor isn't adjustable so is fairly slow for 18650 (which isn't in itself dangerous although it may mean you can't monitor it so well) and still too high for 10440. Mind you at 450mA vs 600 mA which seems very common (e.g. Xtar and Pila) it's not that much slower then other common chargers (well the WF-188 may be somewhat faster because it doesn't use CC/CV too) I think.

BTW as you probably know in terms of cell health there are two basic things, whether it damages the cell enough to risk it blowing up, what you really don't want and whether it reduces cycle life (meaning how the batteries capacity etc varies over cycles). It's my understanding that while you don't want too high, a low charge current isn't good from a cycle life POV either. Then again from what I've read 0.7C is a common recommendation which for 18650 with true 2400mAh or close to it 1680mA would be the sweet spot, only hobby chargers do that. So whether 600mA vs 450mA would really improve cycle life I don't know. (Then of course you've got the complexity of how the unrecommended charging profile would affect cycle life.

P.S. If anyone ever does want to buy from HobbyKing, they have this strange thing where they offer you a lower price after leaving a page open for a while (doesn't have to have focus) for some items. I think some existing customers always get this price if logged in but I don't know the criteria (I made an account but didn't seem to get the low price). It doesn't work with all items, you'll get a message either offering you the price or suggesting you check the forums (which I presume means no discount for this item). It doesn't work for the cheap hobby chargers although does for some of the cable things you may want if you ever do get a hobby charger.

Found this on CPF http://www.batteryspace.com/smartchargersforli-ionbatterypackseries.aspx

These aren't cradle chargers but they're supposed to be CC/CV and have real (I presume) certs. These aren't cradle chargers but harder to screw up then with a hobby charger since there's no settings. In particular the 0.15A one should be good for 10440 and okay for 14500. They also have 1.5A and 1.8A. All only single channel. If you're using 10440 or 14500 you should be able to get cradles relatively easy I presume since you can use most AAA and AA holders.

However they only seem to ship UPS or Fedex when I tried for NZ. I would guess most other international destinations too, although perhaps Canada they might ship something else. So not worth it for us.

Am I correct in assuming a hobby charger could also charge cordless drills? If so I could kill 2 birds with one stone I have seen the Imax B6 for under $30 us in a cpl of places and thinking of getting one.

It'll charge most things as long as it is within the voltage limit for the device.

The commonest ones are 5A max charging current and are clones of the Imax. I got a Turnigy one from Hobbyking for $12.99 plus shipping. It will charge up to 15 NiCd/NiMH cells depending a bit on the input voltage. I use an old PC power supply since it was lying around anyway, The devices that want more than 12V will need a more expensive power supply - and remember that almost all hobby chargers do not come with power supplies.

If it is a more than 18V drill pack carefully check the specs on the charger.

my drills are 12 and 14.4v . Hobby King have a new outlet I think,

brought the Imax from them here http://www.aliexpress.com/product-fm/333416888-IMAX-B6-2S-6S-AC-Charger-with-Leads-LiPo-Balancer-2S-3S-4S-5S-6S-3-wholesalers.html and a power supply.

No shipping on the charger.

Warning Aliexpress has more stuff than DX KD DD and Lightake combined!!

Is that a genuine Imax B6? It seems fairly cheap for a genuine one. The genuine ones have a hologram and number you can check online I believe (see http://www.rcgroups.com/forums/showthread.php?t=746574&page=14). If it's not genuine that price isn't bad although you can get it from eBay for cheaper I think (unless that price actually includes the PSU).

Ebay prices were more or charged shipping. Pretty sure its a fake but as long as it works not too worried. I can check the output. PSU was $9.50 or so shipped.

May be came down on eBay now. I see a bunch of sellers cheaper (total price including shipping) http://shop.ebay.com/i.html?LH_LocatedIn=0&_trkparms=65%253A15%257C66%253A4%257C39%253A1&rt=nc&_nkw=imax%20b6&_adv=1&_dmd=1&_dmpt=Radio_Control_Parts_Accessories&_fsct=&_in_kw=1&_ipg=200&_oexkw=&_okw=imax%20b6&_trksid=p3286.c0.m14.l1513&_pgn=2 e.g.

http://cgi.ebay.com/iMAX-B6-Digital-RC-Lipo-NiMH-3S-Battery-Balance-Charger-/120613804461

http://cgi.ebay.com/IMAX-B6-7-4v-11-1v-14-8v-22-2v-LiPo-RC-Battery-Charger-/170410865279

http://cgi.ebay.com/IMAX-B6-2S-6S-Charger-Leads-LiPo-Balancer-/150484276267

http://cgi.ebay.com/IMAX-B6-2S-6S-AC-DC-Charger-Leads-LiPo-Balancer-/130424880739

http://cgi.ebay.com/iMAX-B6-Digital-RC-Lipo-NiMH-battery-Balance-Charger-/220659154206

http://cgi.ebay.com/IMAX-B6-2S-6S-AC-DC-Charger-Leads-LiPo-Balancer-/300393302501

From a look thorough the completed listings http://completed.shop.ebay.com/i.html?LH_Complete=1&LH_LocatedIn=0&_trkparms=65%253A15%257C66%253A4%257C39%253A1&rt=nc&_nkw=imax%20b6&_adv=1&_dmd=1&_dmpt=Radio_Control_Parts_Accessories&_fsct=&_in_kw=1&_ipg=200&_oexkw=&_okw=imax%20b6&_sc=1&_sop=15&_trksid=p3286.c0.m14.l1581&_udhi=&_udlo=&_pgn=2 you could probably get it $22-$23.50 all up if you're willing to try auctions (seems to be quite a few sold around this price and looking at current listings there are quite a lot so I don't think you'll have to wait long)

Now the challenge is battery holders..

There was a lot of discussion on this topic on CPF a couple of years ago. I use a lot of magnets. Problem is, some 18650s bases are only weakly magnetic, the alloy they use clearly wasn't chosen for its ability to stick to a magnet.

For multiple 18650s something could be done with these and some spring contacts. I keep my 18650s in these boxes so I have several of them.

For other sizes these leads with magnets on the end are very handy. The guy who owns the patent used to sell them on ebay - a quick search for Magtrix (the brand name) turned up nothing.

Will have to mod them but they should work

Right one a C battery holder and left is a CR123 holder?

I'm actually somewhat surprised that 18650 holders are so hard to come buy in small quantities except for those extremely expensive home made stuff on CPF etc. Been thinking of building a reprap one day for a while now (unrelated to flashlights), when/if I do shouldn't be too hard to make a fairly cheap holder.

Edit: Actually remember now Digikey has them but unless you're buying lots of stuff from them shipping kills it. I was more thinking of the Chinese stuff like from eBay or DX

Edit2: Ooops actually you can get them from eBay. Not cheap tho (US$13.99 total for 5) and you need to buy 5. You can buy 12 or so C battery holders for about the same price

BTW let me know how it goes. I don't have a hobby charger, may get one in the future but need a holder for a single 18650 for a DIY project. I have various ideas but interesting to see what works. Other then modifying a cheap battery holder of some kind, I'm also thinking of just working something up with a spring and some other contact and a bunch of plastic and perhaps a plastic soft drink bottle top or two. Another idea is one of those cheap 18650 boxes I got from BuyInCoins (got 8 but only need 2) although there isn't much space in those.

Old4570 on Jayki did find some, but they weren't really long enough.

http://www.jayki.com/9607

The link to ebay where he got them.

http://cgi.ebay.com.au/5X-Case-Box-18650-3-7V-Rechargeable-Lithium-Battery-/260648272217?pt=US_Batteries#ht_3289wt_913

Postage is taking the mickey as usual...

Thanks, missed those. These ones I found on eBay are even more http://cgi.ebay.com/5-x-Holder-18650-3-7V-Rechargeable-Lithium-Battery-/190434594119 Spring looks like it might be longer so perhaps less likely to be too short. Both too expensive for my liking particularly since I don't want that many. Mind you, even digikey seems expensive in large quantities let alone small. Perhaps someone should do a bulk buy from China? http://www.diytrade.com/china/4/products-list/0-k-c-1/18650_battery_holder.html http://www.alibaba.com/product-gs/278975826/1S1P_18650_Battery_Holder.html http://www.china-direct-buy.com/v/4/product_detail/6480368/18650_3_7V_Lithium_Battery_Case_Holder.html (http://www.china-direct-buy.com/v/4/product_detail/6762289/18650_3_7V_Lithium_Battery_Holder_with_PCB_Mounting.html are the same as the first one) :-P

However looking a bit more it seems the eBay one I found have a store http://www.virtual-village.com.au/5-x-holder-for-18650-3-7v-rechargeable-lithium-battery-006310-012.html and it's cheaper there if you exclude insurance. And a quick search found a 20% coupon VVN392R which seems to still work (item price only). Ends up AU $10.18 all up or ~US$9.13 or less then US$2 for one which ain't too bad I guess particularly given the wholesale price for those seems to be US$0.735. They also have a UK store but it ends up a bit more there even excluding insurance. (And on their US store it doesn't seem to exist at all.)

Having just looked at Virtualvillage's UK website they are taking the mickey on UK postage. But ordered 5 of those as they'll make life easier.

One on the right is a 4 x C cell on the left a single C cell. 75cents for the single $1.25 for the 4x . Postage on the Ebay holders kills the deal for me. Will post some pics when I have it setup