andrewnewman
Enlightened
This post is neither a formal review nor a hobby charger how-to (there are already many excellent threads that cover this). This is merely my observations having used this inexpensive charger for a variety of things related to powering flashlights.
The Eco-6 50W charger from Hobby King costs about 18 dollars plus 10 dollars airmail from Hong Kong. As this total was about twice what I paid for my (in)famous WF-139, I regard it as a serviceable upgrade. I am retiring the Ultrafire charger and using this to supplement my excellent Maha C-9000 charger.
So the box arrived at the post office about a week ago and since then I have been charging everything in sight. All of my cells are either loose or in a flashlight carrier. I have, thus far, charged Li-Ion RCR123 cells and 18650s as single cells and various AA and AAA NiMH batteries in various serial configurations.
The charger itself seems well made for the price. The membrane buttons are as good as any, the display is bright blue and the buttons repeat when held down. Also the annoying beep when a button is pressed can be turned off. The tactile feedback is sufficient. The charger has a tiny fan inside that slowly comes up to a mini-roar when charging commences. I am not convinced the fan is needed given how cool the charger remains. It has 4 rubber standoff feet and I keep it on a piece of scrap floor tile. The back is the only part that is made of metal but it seems to be a very effective heat sink.
Since every hobby charger seems to have the same control software (or similar copies) and the same basic manual I should point out a couple inconsistencies in this particular one.
1. None of the manuals seem clear on this point but from experimentation, the safety timer and capacity cut-off settings are only applicable to Nickel based charging profiles. They protect against a missed -dV termination and aren't needed for Lithium charging.
2. The manual claims the display shows the battery voltage but it appears to show the charging voltage instead. When charging NiMH or Lithium during the 'CC' phase, the charger periodically drops the current to zero for about 4-5 seconds at the first few minutes of the charge cycle. If you watch closely you can read what I believe to be the battery voltage during these lulls.
3. There is a reference to Manual and Automatic NiMH charging modes but my unit only has Manual. Im not sure exactly what Automatic might do but in manual, the only setting you can adjust is the charge current.
Charging Li-Ion batteries is straightforward and the unit provides comforting feedback. As has been mentioned, the LiPo profile on these chargers is the most appropriate for modern LiCo batteries (4.2V charging cap CCCV). I tend to charge Li-Ion batteries at 0.5C or below for two reasons. First it seems to be easier on the batteries (they never get even a little warm unless they are near end of life). Second since the hobby charger uses a percentage (10%) of the charge current during CV to decide to terminate, the lower the charge current the closer the battery is to terminating to manufacturer's specification. For example, I have a 2600 mAh 18650 from LG Chemical whose spec sheet says to charge at 0.5C and terminate when the current drops to 50mA. If I set the charge current at 800mA I end up with a charge rate well below 0.5C but I will terminate at 80mA.
Charging NiMH batteries is a bit less comforting (you can take my MAHA when you pry it from my cold dead hands...). The charger doesnt care how many cells are in series (unlike LiIon charging) and happily applies a charge voltage sufficient to meet the configured charge current requirement. The device has two previously mentioned safety features (maximum capacity / maximum time) but they have to be set globally rather than per-profile so they are a pain to use if you regularly charge different capacity batteries at different charge rates. The device terminates using -dV/dt and allows you to set the NiMH and NiCd sensitivity (default for NiMH is 7mV which seems pretty standard). I have had good luck charging 4S AA cells in a small carrier for my bicycle headlamp and 8S AA cells in the carrier for my Fenix TK-45. Both of these configurations were charged at 0.5C and terminated predictably. Single and 2S (held together with magnets) AA configurations were hit and miss. Newer batteries tended to terminate (mostly) reliably at 0.5C and reliably at 1C. Older batteries frequently miss termination despite charge rate. LSDs work generally far better than non-LSD NiMH in this regard. AAA batteries are even less reliable when charged as single cells. Here there is a high likelihood of just cooking the battery if you arent paying attention at 0.5C and a distinct possibility (~25-30%) even at 1C. Not likely to give up my MH-C9000 any time soon.
Anyway, 28 bucks seems like a good deal for this small flexible charger. I will never use the temperature probe, the balance connectors or the USB connector and it is doubtful I will charge many Pb batteries (or NiCd batteries for that matter) but it's nice to have the flexibility. Hobby King seems like a pretty good company to do business with. You sure have to be patient on delivery (~4 weeks in my case) but the price is right.
The Eco-6 50W charger from Hobby King costs about 18 dollars plus 10 dollars airmail from Hong Kong. As this total was about twice what I paid for my (in)famous WF-139, I regard it as a serviceable upgrade. I am retiring the Ultrafire charger and using this to supplement my excellent Maha C-9000 charger.
So the box arrived at the post office about a week ago and since then I have been charging everything in sight. All of my cells are either loose or in a flashlight carrier. I have, thus far, charged Li-Ion RCR123 cells and 18650s as single cells and various AA and AAA NiMH batteries in various serial configurations.
The charger itself seems well made for the price. The membrane buttons are as good as any, the display is bright blue and the buttons repeat when held down. Also the annoying beep when a button is pressed can be turned off. The tactile feedback is sufficient. The charger has a tiny fan inside that slowly comes up to a mini-roar when charging commences. I am not convinced the fan is needed given how cool the charger remains. It has 4 rubber standoff feet and I keep it on a piece of scrap floor tile. The back is the only part that is made of metal but it seems to be a very effective heat sink.
Since every hobby charger seems to have the same control software (or similar copies) and the same basic manual I should point out a couple inconsistencies in this particular one.
1. None of the manuals seem clear on this point but from experimentation, the safety timer and capacity cut-off settings are only applicable to Nickel based charging profiles. They protect against a missed -dV termination and aren't needed for Lithium charging.
2. The manual claims the display shows the battery voltage but it appears to show the charging voltage instead. When charging NiMH or Lithium during the 'CC' phase, the charger periodically drops the current to zero for about 4-5 seconds at the first few minutes of the charge cycle. If you watch closely you can read what I believe to be the battery voltage during these lulls.
3. There is a reference to Manual and Automatic NiMH charging modes but my unit only has Manual. Im not sure exactly what Automatic might do but in manual, the only setting you can adjust is the charge current.
Charging Li-Ion batteries is straightforward and the unit provides comforting feedback. As has been mentioned, the LiPo profile on these chargers is the most appropriate for modern LiCo batteries (4.2V charging cap CCCV). I tend to charge Li-Ion batteries at 0.5C or below for two reasons. First it seems to be easier on the batteries (they never get even a little warm unless they are near end of life). Second since the hobby charger uses a percentage (10%) of the charge current during CV to decide to terminate, the lower the charge current the closer the battery is to terminating to manufacturer's specification. For example, I have a 2600 mAh 18650 from LG Chemical whose spec sheet says to charge at 0.5C and terminate when the current drops to 50mA. If I set the charge current at 800mA I end up with a charge rate well below 0.5C but I will terminate at 80mA.
Charging NiMH batteries is a bit less comforting (you can take my MAHA when you pry it from my cold dead hands...). The charger doesnt care how many cells are in series (unlike LiIon charging) and happily applies a charge voltage sufficient to meet the configured charge current requirement. The device has two previously mentioned safety features (maximum capacity / maximum time) but they have to be set globally rather than per-profile so they are a pain to use if you regularly charge different capacity batteries at different charge rates. The device terminates using -dV/dt and allows you to set the NiMH and NiCd sensitivity (default for NiMH is 7mV which seems pretty standard). I have had good luck charging 4S AA cells in a small carrier for my bicycle headlamp and 8S AA cells in the carrier for my Fenix TK-45. Both of these configurations were charged at 0.5C and terminated predictably. Single and 2S (held together with magnets) AA configurations were hit and miss. Newer batteries tended to terminate (mostly) reliably at 0.5C and reliably at 1C. Older batteries frequently miss termination despite charge rate. LSDs work generally far better than non-LSD NiMH in this regard. AAA batteries are even less reliable when charged as single cells. Here there is a high likelihood of just cooking the battery if you arent paying attention at 0.5C and a distinct possibility (~25-30%) even at 1C. Not likely to give up my MH-C9000 any time soon.
Anyway, 28 bucks seems like a good deal for this small flexible charger. I will never use the temperature probe, the balance connectors or the USB connector and it is doubtful I will charge many Pb batteries (or NiCd batteries for that matter) but it's nice to have the flexibility. Hobby King seems like a pretty good company to do business with. You sure have to be patient on delivery (~4 weeks in my case) but the price is right.
