Thanks guys but I already have both chargers and was just trying to find out if any one new any issues with them. It would help out others looking for a charger if they had some insight first. I know there are better chargers but these two come up a lot when looking for chargers.
On a couple of Flashlight Forums, I read that there were 3 or 4 versions of the WF-139 over the past few years. Some mentioned that after completing a charge it would then trickle charge, leading to overcharging. The batteries when pulled from the charger were hot. Some said theirs were not hot. ? which version ? Now, I couldn't get specific answers on what version did what and if the final version fixed the issues. Also, couldn't find how to identify the versions.
Charge times are listed below although my TR-001 is a slow charger and takes 5 to 7hrs for an 18650 2400mah. The WF-139 is a Rapid Charger which I haven't tried yet. Still sitting on my desk. See Wikipedia's Rapid charger statement.
This came from Wikipedia Lithium-ion Battery:
Charging procedure
Stage 1: Apply charging current until the voltage limit per cell is reached.[48]
Stage 2: Apply maximum voltage per cell limit until the current declines below 3% of rated charge current.[48][unreliable source?]
Stage 3: Periodically apply a top-off charge about once per 500 hours.[48][unreliable source?]
The charge time is about three to five hours, depending on the charger used. Generally, cell phone batteries can be charged at 1C and laptop-types at 0.8C, where C is the current that would discharge the battery in one hour. Charging is usually stopped when the current goes below 0.03C but it can be left indefinitely depending on desired charging time. Some fast chargers skip stage 2 and claim the battery is ready at 70% charge.[48][unreliable source?] Laptop battery chargers sometimes gamble, and try to charge up to 4.35 V then disconnects the battery. This helps to compensate for the battery's internal resistance and charges up to 100% in short time.
Top-off charging is recommended when voltage goes below 4.05 V/cell.[48][unreliable source?]
Lithium-ion[which?] cells are charged with 4.2 ± 0.05 V/cell, except for military long-life cells where 3.92 V is used for extending battery life. Most protection circuits cut off if either 4.3 V or 90 °C is reached. If the voltage drops below 2.50 V per cell, the battery protection circuit may also render it unchargeable with regular charging equipment. Most battery protection circuits stop at 2.7–3.0 V per cell.[48][unreliable source?]
For safety reasons it is recommended the battery be kept at the manufacturer's stated voltage and current ratings during both charge and discharge cycles.
"End of Wikipedia's Quote"
Now.... this thread is to help others trying to decide. I'm happy with the cheap crappy TR-001. The only reason I have the WF-139 is because I ordered it 2 months ago, and after two weeks when it didn't even ship, I canceled a got a refund. And now after 9 weeks, it showed up at my door step.
Like I said before, I know there are better chargers. Just trying to get some info or comparisons on the two chargers mentioned above.
Thank You Guys. Appreciate all your views.
