I recently saw this charger in threads here and looked it up because I've been given some laptop batteries and also been playing with power banks and USB powered devices and needed to check the capacity of batteries I have as some seemingly don't last too long and others seem to discharge themselves sitting for a few months. I was considering the Opus BT-C3100 v2.2 but finances decided against that and a tempting offer on Gearbest for about $10 and some change made me risk it.
First impressions:
1) Bigger than expected but then it is my first Lithium Ion charger.
2) Decent quality construction, would probably sell in stores for 2.5 times as much I figure.
3) Interface was easy to get used to since I already have an old Lacrosse BC-900 which works fine.
I've analyzed about half a dozen 18650s so far and the charger does well at doing so but I realized after testing a few of them off the charger that I had a small manufacturing "defect" that I guess many of not most of these chargers have in that the voltage readout is a little higher than actual. Mine was about 0.6v high compared to my Fluke 117 meter. I also checked it against my old Craftsman meter which measured 0.8v lower and a cheap red Harbor Freight (freebie) meter that measured 0.5v lower.
After I realized this I searched the internet and found a mod that required soldering a 68k ohm resistor to two smd resistors "ends". If you take the back plate (4 screws) off you can see it with either good eyes or a magnifying glass. This repair is not too difficult to someone who is pretty good with a soldering iron and it "adjusts" the voltage about 0.5v upward on the charger (to charge cells higher voltage). My charger seems to stop at about 4.21v so I'm pretty much within 0.1v of 4.2 instead of 4.14v.
I tried the power bank function and it seems very good with just a short test I used a USB LED light that takes 75ma and one that takes about 900ma and both worked fine and the output voltage stayed constant at 5.1v unlike some of my power banks that drop under that much load as much as half a volt or more. I should have tested it using my usb load tester (resistors) that simulates 1A and 2A loads I will try that if someone is interested but I'm pretty sure it will do 2A I think it is rated for 2.1A in the manual. I haven't tried the micro USB power input mode. When I tried the power bank mode I did unplug it and noticed that it was harder to change modes (readout) from Amps to volts to watch the battery voltage you have to press and hold longer to do that like there is huge lag going on.
Pros:
1) Smallest analyzing charger out there that I know of.
2) Well built quality construction.
3) Large enough display to see at a short distance (6 feet for main numeric readout)
4) Well lit backlight with 3 digit resolution 3.456 etc.
5) 12v 5.5mm plug power input from brick and 5v micro USB inputs
6) USB power bank function with decent output that allows monitoring voltages and currents of both battery and USB outputs.
7) Charges Nimh and Nicad and supports 3.7 and 3.8v lithium battery types (4.2V, 4.35V?)
8) Able to "refresh" Nimh batteries and test capacity of Lithium batteries
9) Multiple charge and discharge rates up to 2A on Nimh and 1.6A on lithium charging and 1A on Nimh and 700ma on lithium discharging.
10) Has impedance test that is separate but also scrolling through readouts during operation it is always listed and most of the time the number is the same as running the separate test alone. This is useful to help determine battery health and explain some battery problems like higher than normal self discharge.
CONS:
1) No rubber feet on charger so it can slide around and possibly scratch/mar surfaces it is placed upon.
2) Cord placement is not optimal at all, it is like the sockets were put on the circuit board as an afterthought with the 12v power on the right side near the front, the USB port on the left side near the back and the micro USB power input in the very front edge. I would have put the 12v power out the very back and the micro USB out one side near the back and the USB port either in front or near the front edge but as it is makes it hard to place in a "busy" location with other chargers and devices it has to stick out front or allow more clearance on the side of the 12v input.
3) Display is tilted but not enough if it is on a table and you are at a 45 degree angle it is harder to read I put some rubber blocks on bottom near the back to tilt it up more to reduce the "ghost" images of unpowered LCD "pixels" etc.
4) Backlight is ALWAYS ON, even when no power it attached and powered by the battery in it. It doesn't shut off at all and at night you either have to put something over it or unplug it if it is nearby as it does put out enough to be a nightlight. I may install an switch to turn it on/off or reduce the power to the LEDs some as ti doesn't need to be as bright as it is.
5) Higher rates on lithium batteries would be nice... 2A charge and 1A discharge would help to both analyze and charge larger batteries faster but 1.6A charge and 0.7A discharge is still useful if you need to go that much faster best to either buy multiple C100s or a 4 bay charger/analyzer.
6) Analyzer doesn't display ongoing mah while discharging so you don't know how things are going until either it is done discharging AND then recharging and says FULL or you watch the voltage and discharge/charge text at top which is smaller and not as easily seen from a distance.
7) Final charging voltage varies from what I've read with several of these off by 0.05v which may not seem too huge of a number but it can "add" 5% or so capacity to your lithium batteries and a 3500mah battery it would add 175mah more which is an extra hour on low mode on my cheap 18650 flashlights and could be several hours or more powering a USB LED light. I made a USB light that takes 14ma of power and that extra could run if for half a day.
8) Online PDF manual not available (YET) from the manufacturer. I have PDF manuals for most of my electronic stuff and appliances and find it very handy to not have to dig through either filing cabinet or empty boxes piled up somewhere to find out how to use a mode or see specifications for the device. I can read a PDF manual (or even a text file) in 30 seconds vs 15 minutes. The manual for this is readable but could be written better as it hops around putting stuff not in a more useful order with most of the first two pages safety tips and then going into using the modes before even discussing the display itself which is after explaining the USB mode. It could use a few more charts better written too for more instant information.
Notes: Comes in a ~6x6x2 inch nice box, purple with pictures and lightning bolt graphics that has a "tuckable" front flap. Manual is essentially the size of two sheets of normal copy paper side by side folded in half and half again printed on both sides. AC charger is a wallwart with sideways plug (US) which allows a smaller footprint on power strips and has a sideways 5.5mm? DC plug so you should be able to replace it and also get a 12vdc car adapter (needs to be 1A at least capable) you can also use a 2A micro USB cable setup either AC or 12vdc powered. USB mode requires you to press and hold the "current" button till it says "O F F" which is skewed vertically on the right side of the display. You then press the current button again till it says ON and it takes a few seconds for the voltage to show up in that section along with the amperage which is 0.0 till a load is applied. The Amps resolution is only 1 decimal but still useful enough for most uses there isn't room for more digits there.
I recommend this charger at the price I paid for it (under $11) but if you were to buy it at close to $20 I would recommend you consider a 4 cell model. The shipping time from Gearbest was not too bad about 2 weeks but from what I've read YMMV on that. At the time I bought this there was very limited amount of places to get this and they were all based in China I believe but I think mine was shipped from Germany or maybe it was shipped from Germany to China back to me? Don't quote me on that I threw away the bubblewrap envelope already.
First impressions:
1) Bigger than expected but then it is my first Lithium Ion charger.
2) Decent quality construction, would probably sell in stores for 2.5 times as much I figure.
3) Interface was easy to get used to since I already have an old Lacrosse BC-900 which works fine.
I've analyzed about half a dozen 18650s so far and the charger does well at doing so but I realized after testing a few of them off the charger that I had a small manufacturing "defect" that I guess many of not most of these chargers have in that the voltage readout is a little higher than actual. Mine was about 0.6v high compared to my Fluke 117 meter. I also checked it against my old Craftsman meter which measured 0.8v lower and a cheap red Harbor Freight (freebie) meter that measured 0.5v lower.
After I realized this I searched the internet and found a mod that required soldering a 68k ohm resistor to two smd resistors "ends". If you take the back plate (4 screws) off you can see it with either good eyes or a magnifying glass. This repair is not too difficult to someone who is pretty good with a soldering iron and it "adjusts" the voltage about 0.5v upward on the charger (to charge cells higher voltage). My charger seems to stop at about 4.21v so I'm pretty much within 0.1v of 4.2 instead of 4.14v.
I tried the power bank function and it seems very good with just a short test I used a USB LED light that takes 75ma and one that takes about 900ma and both worked fine and the output voltage stayed constant at 5.1v unlike some of my power banks that drop under that much load as much as half a volt or more. I should have tested it using my usb load tester (resistors) that simulates 1A and 2A loads I will try that if someone is interested but I'm pretty sure it will do 2A I think it is rated for 2.1A in the manual. I haven't tried the micro USB power input mode. When I tried the power bank mode I did unplug it and noticed that it was harder to change modes (readout) from Amps to volts to watch the battery voltage you have to press and hold longer to do that like there is huge lag going on.
Pros:
1) Smallest analyzing charger out there that I know of.
2) Well built quality construction.
3) Large enough display to see at a short distance (6 feet for main numeric readout)
4) Well lit backlight with 3 digit resolution 3.456 etc.
5) 12v 5.5mm plug power input from brick and 5v micro USB inputs
6) USB power bank function with decent output that allows monitoring voltages and currents of both battery and USB outputs.
7) Charges Nimh and Nicad and supports 3.7 and 3.8v lithium battery types (4.2V, 4.35V?)
8) Able to "refresh" Nimh batteries and test capacity of Lithium batteries
9) Multiple charge and discharge rates up to 2A on Nimh and 1.6A on lithium charging and 1A on Nimh and 700ma on lithium discharging.
10) Has impedance test that is separate but also scrolling through readouts during operation it is always listed and most of the time the number is the same as running the separate test alone. This is useful to help determine battery health and explain some battery problems like higher than normal self discharge.
CONS:
1) No rubber feet on charger so it can slide around and possibly scratch/mar surfaces it is placed upon.
2) Cord placement is not optimal at all, it is like the sockets were put on the circuit board as an afterthought with the 12v power on the right side near the front, the USB port on the left side near the back and the micro USB power input in the very front edge. I would have put the 12v power out the very back and the micro USB out one side near the back and the USB port either in front or near the front edge but as it is makes it hard to place in a "busy" location with other chargers and devices it has to stick out front or allow more clearance on the side of the 12v input.
3) Display is tilted but not enough if it is on a table and you are at a 45 degree angle it is harder to read I put some rubber blocks on bottom near the back to tilt it up more to reduce the "ghost" images of unpowered LCD "pixels" etc.
4) Backlight is ALWAYS ON, even when no power it attached and powered by the battery in it. It doesn't shut off at all and at night you either have to put something over it or unplug it if it is nearby as it does put out enough to be a nightlight. I may install an switch to turn it on/off or reduce the power to the LEDs some as ti doesn't need to be as bright as it is.
5) Higher rates on lithium batteries would be nice... 2A charge and 1A discharge would help to both analyze and charge larger batteries faster but 1.6A charge and 0.7A discharge is still useful if you need to go that much faster best to either buy multiple C100s or a 4 bay charger/analyzer.
6) Analyzer doesn't display ongoing mah while discharging so you don't know how things are going until either it is done discharging AND then recharging and says FULL or you watch the voltage and discharge/charge text at top which is smaller and not as easily seen from a distance.
7) Final charging voltage varies from what I've read with several of these off by 0.05v which may not seem too huge of a number but it can "add" 5% or so capacity to your lithium batteries and a 3500mah battery it would add 175mah more which is an extra hour on low mode on my cheap 18650 flashlights and could be several hours or more powering a USB LED light. I made a USB light that takes 14ma of power and that extra could run if for half a day.
8) Online PDF manual not available (YET) from the manufacturer. I have PDF manuals for most of my electronic stuff and appliances and find it very handy to not have to dig through either filing cabinet or empty boxes piled up somewhere to find out how to use a mode or see specifications for the device. I can read a PDF manual (or even a text file) in 30 seconds vs 15 minutes. The manual for this is readable but could be written better as it hops around putting stuff not in a more useful order with most of the first two pages safety tips and then going into using the modes before even discussing the display itself which is after explaining the USB mode. It could use a few more charts better written too for more instant information.
Notes: Comes in a ~6x6x2 inch nice box, purple with pictures and lightning bolt graphics that has a "tuckable" front flap. Manual is essentially the size of two sheets of normal copy paper side by side folded in half and half again printed on both sides. AC charger is a wallwart with sideways plug (US) which allows a smaller footprint on power strips and has a sideways 5.5mm? DC plug so you should be able to replace it and also get a 12vdc car adapter (needs to be 1A at least capable) you can also use a 2A micro USB cable setup either AC or 12vdc powered. USB mode requires you to press and hold the "current" button till it says "O F F" which is skewed vertically on the right side of the display. You then press the current button again till it says ON and it takes a few seconds for the voltage to show up in that section along with the amperage which is 0.0 till a load is applied. The Amps resolution is only 1 decimal but still useful enough for most uses there isn't room for more digits there.
I recommend this charger at the price I paid for it (under $11) but if you were to buy it at close to $20 I would recommend you consider a 4 cell model. The shipping time from Gearbest was not too bad about 2 weeks but from what I've read YMMV on that. At the time I bought this there was very limited amount of places to get this and they were all based in China I believe but I think mine was shipped from Germany or maybe it was shipped from Germany to China back to me? Don't quote me on that I threw away the bubblewrap envelope already.
