HobbyKiing 4 channel charger $70+ ship

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okwchin
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HobbyKiing 4 channel charger $70+ ship

4 channel from hobbyking (up to 6 individually balanced cells each but we dont need to use that feature)

To me, I see this working in the context of torches for simply charging individual cells per channel. This would provide individual cell data, and you can charge different cells with each channel. Key data would be voltage, current rate, and most importantly, capacity put into each cell.

This has advantages over a normal charger with balance leads because you know the current capacity measurement is accurate if your charging only one cell per charger, as opposed to 3 on the same "capacity" measurement.

 

http://www.hobbyking.com/hobbycity/store/uh_viewItem.asp?idProduct=16374

"like everyone else - I’m looking for my next “last” flashlight" -  ohnonothimagain

Edited by: okwchin on 06/16/2011 - 01:54
FlashPilot
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It does look perfect for individual cell charge/discharge stats. I couldnt find a link to the manual. It recharges LIPO but will it charge LICO to 4.2V?

Don
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In most of these, you just tell it that it is charging LiPo which go to 4.2V rather than Li Ion which they charge to 4.1V. 

 

You get a very large increase in cycle life by only charging to 4.1V with about a 10% (From my admittedly poor memory) decrease in runtime. If you store your cells charged as I tend to do then other factors than cycle life will determine how long the cell lasts.

 

The numbers from my light tests are always to be found here.

https://spreadsheets.google.com/ccc?key=0ApkFM37n_QnRdDU5MDNzOURjYllmZHI...

okwchin
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I tend to store cells charged, and apparently that means you will lose something like 20% of capacity a year, permanently.

But more often than not, If i leave them uncharged, I usualyl have to quick charge them and thats probably more damaging. lol.

 

 

Interms of chemistry, a CC/CV charger doesn't really need to know the chemistry. Charging termination is simply just the theoretical voltage, for which I just set LiPo - 4.2V. 

"like everyone else - I’m looking for my next “last” flashlight" -  ohnonothimagain

FlashPilot
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While looking online for instructions on this charger, I discovered that they apparently dont come with any at all!

Then I came across this: what appears to be a nearly identical charger that costs more and said to be a rebranded Turnigy charger. The reviews were less than pleasing since the accuracy from channel to channel gave mixed results. There is apparently a way to calibrate the charger, but since this comes new from the factory, you would think it would already come calibrated. Accuracy in charging LICO's is very important, which is why most of us with cheap Chinese chargers (that dont want exploding high powered LICO cells in our homes) check cell voltages constantly during the charge process. It is unclear as to weather or not the less expensive charger the OP mentioned is in fact the same charger or shares the same internals and firmware options & version.

Link for the manual for the other charger in PDF format. A link from RCGroups shows others replacing resistors to make balance charge voltage more consistent and accurate between cells.

Im still unsure how accurate any of these would be, even for independent single cell charging, and assuming calibration adjustments were enabled through the firmware.

okwchin
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The concern with accuracy is always what bothers me with these chargers. Interms of manual, I dont think you need one though, they all seem very intuitive to use.

 

For the reason of accuracy, I have a iCharger, which has a degree of software voltage calibration which works. I remember other more budget models which provide trimpots still not having satisfactory levels of adjustability. The cheaper chargers from HK stores scare me even more with higher number of reported floating voltage issues.

"like everyone else - I’m looking for my next “last” flashlight" -  ohnonothimagain

FlashPilot
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It was a good idea, but poorly executed with the cheapest of components available to pinch a few cents during the manufacturing process. After some more research, several hobby voltage/amperage monitoring devices report well outside of a range of what anyone would consider "accurate enough" to fulfill its intended duty. Sorry but +/- .5V that fluctuate during operation puts a lot of these chinese products in the rubbish category.

Ive heard about the iCharger before (probably on this forum). Can you tell us more about it and why you like it? I dont mind making my own charging looms as long as I can find instruction on how to.