I have an Efest LUC V4 that's gotta be at least 5 years old now. Maybe even 6? It doesn't take 21700 batts but the newer model LUC V4 HD does. Don't know if it's any good, though.
I'm thinking of another backup charger, and checking out that luv v4 HD, looks good for 21700s, but I want the option to charge at 0.5 amps, and that one looks like it's either 1 or 2 amp charging only. Am I reading that right?
I'm thinking of another backup charger, and checking out that luv v4 HD, looks good for 21700s, but I want the option to charge at 0.5 amps, and that one looks like it's either 1 or 2 amp charging only. Am I reading that right?
If you want an affordable charger that takes 21700 batts, the Opus BT-C3100 is on sale at 18650batterystore for $28. It has a lot of features and can be set as low as 0.2mA. It does 0.2ma, 0.3ma, 0.5ma, 0.7ma, 1A, 1.5A & 2A, However 1, 1.5 and 2A depends on how many batteries you're charging. Each bay's current charging rate can be set independently, unlike the LUC V4 (and I assume the LUC V4 HD)
If you are interested, I suggest you read this post I made to @hittman as there are somethings you may want to know about it which may or may not matter to you.
Lots of people like the Opus BT-C3100 but it has it's drawbacks for some people depending on what they want in a charger.
To determine CDR, you need the ability to discharge at high currents and a CBA IV is good for that. But you also need the ability to accurately measure cell temperature, because that tends to be the limiting factor.What's the most affordable, yet accurate combination of equipment to test the CDR, internal resistance, and capacity of a lithium ion battery?
I was looking at the CBA IV - Computerized Battery Analyzer. Not sure yet if it will check off all those boxes or if there is a better solution.
I just got the HD in a few weeks ago and liking it. Does fine for someone like me who isn't interested in all the tech stuff. I charge everything at 0.5 but it has 0.25-2 amp charging. Miss my luc 6 since switching over to 21700.I have an Efest LUC V4 that's gotta be at least 5 years old now. Maybe even 6? It doesn't take 21700 batts but the newer model LUC V4 HD does. Don't know if it's any good, though.
Unless you need your batts to charge faster it is always (as a rule) to charge your batteries at the lowest rate possible.I just got the HD in a few weeks ago and liking it. Does fine for someone like me who isn't interested in all the tech stuff. I charge everything at 0.5 but it has 0.25-2 amp charging. Miss my luc 6 since switching over to 21700.
But you also need the ability to accurately measure cell temperature, because that tends to be the limiting factor.
At 0.5 they charge during my at home/ waking hours. Tried the 0.25 and it just took too long, found myself forgetting about it.Unless you need your batts to charge faster it is always (as a rule) to charge your batteries at the lowest rate possible.
Then 0.5 is the right setting for you.At 0.5 they charge during my at home/ waking hours. Tried the 0.25 and it just took too long, found myself forgetting about it.
I'm not sure that's correct. I don't recall where I read it, but charging too slowly is not beneficial and may even be mildly detrimental.Unless you need your batts to charge faster it is always (as a rule) to charge your batteries at the lowest rate possible.
I have an Efest LUC V4 that's gotta be at least 5 years old now. Maybe even 6? It doesn't take 21700 batts but the newer model LUC V4 HD does. Don't know if it's any good, though.
Most of what I read suggested the lower the rate the less detrimental affects there are on the battery (heat). That said, I suspect there is little impact between 0.25 and 0.5. And your rule of thumb is probably a good one in absence of a $247 million federal grant to study it at Carnegie Mellon University.I'm not sure that's correct. I don't recall where I read it, but charging too slowly is not beneficial and may even be mildly detrimental.
My personal rule of thumb is: If there's no noticeable (to the touch) temperature rise of the cells during charging, there's no benefit in charging more slowly than that. The chargers I use all support 0.25, 0.5 and 1.0 amps. At 0.5A there is no noticeable temperature rise, but at 1.0 there is, so I use 0.5 unless I'm in a hurry.