The making of the BLF UC4 charger: the start of a new venture, INTEREST LIST, UPDATE 7 (Well, ramping stopped :/ )

Put me down for one. Thanks!

Please add me to the list. I am interested in getting one.

Please add me to the list. For anyone helping with this, thank you for your time

I'm interested in one.

Thank you.

Please add me to list for one.

Came here to say that, well, the list of default charge currents needs at least these fixes: the 0.8 A value be reduced to 0.7 A (so the jump between 0.5 and 1 A bears about geometric progression), and a new 0.35 A value be added between 0.25 and 0.5 A, for the same reason (a fully configurable charge currents list via advanced menu would be praiseworthy). Thanks.

Interested in one, thank you.

This is excellent and I hope all comes out well. I’m very interested in one so put me on the list please.

I’m a noob but interested. Coming from RC hobbies where NiMh and Li-Po cells conditioned with better chargers outperforms those same cells charged on regular low end chargers. It would be interesting to see how these chargers will affect the discharge rates of the li-Ion batteries used in these newer flashlights.

Hmmm. I assume that there’s scientific evidence available for such magic? What sort of “conditioning” is going on here, as that word is often mis-used for marketing purposes?

YogibearAl I was also going to chime in and say something hours ago, yet refrained. But now that I'm here, and also given leftdisconnected's statement, I'll say that concerning standard li-ion cells (not LiFePO4) I don't see how a charger can increase their performance with the exception of overcharging the cells. Standard li-ion chemistries will grab extra voltage, capacity and energy if overcharged, at a reduced lifespan price. Depending on cell chemistry, type and or quality this may also involve other risks (years ago I received some fake Samsung ICR18650-30B cells which died upon charging them to 4.35 V, for example).

Please add me to the list for qty. 1.

Thanks!

I’d be interested in one of these. +1 Masejoer

With RC’s it’s more about the health of the entire multi cell pack. A properly balanced pack probably does perform longer and better. I admit differences were seen less with LiPo packs that were well matched and balanced.
With NiMh that I have more experience with, a good charger has its benefits. I was working with some friends who bought a generic charger for their battery packs, their packs consistently ran longer and their cars faster when charged with my Intengy charger. Now we didn’t measure the output or discharge rates, but after I ran through some discharge charge cycles their capacity also increased. I know this is all annectdotal, but I never thought to do individual cell testing back when I was into RC. Today I would probably do a more detailed analysis to understand it better. I was just hoping something like this was similar in these newer lithium cells used today. If not that is fine too. I currently own an Xstar VC4S charger that allows up to 3A charging of single cells. Based on what I’m hearing charging single lithium cell at 2-3A is not advised? Like I mentioned, I’m new to these batteries and am reading up in this forum and others. So any knowledge would be appreciated.

Thanks,

I already fixed your quote YogibearAl. ;-)

Series packs are different beasts, particularly with the aforementioned standard li-ion (4.2+ V) chemistries. This is because high voltage li-ion does not tolerate overcharging, i.e. it is quite harmful. In my opinion, standard li-ion balance boards (or BMS boards with balance) do a poor job in this respect due to them performing controlled battery stage or cell bleeding at an already high voltage while the charger may still be pumping current into the series pack. Much better balance algorithms could be devised.

Topping up a Ni-MH or Ni-CD series pack at a gentle, low charge rate balances it, but of course takes quite a bit of time. In an old DeWalt user manual it is said to keep the battery in the charger for up to 8 additional hours after a full charge, that time frame being employed in refresh/tuning mode, which charges battery at ≈5% of standard rate (150 mA in a 2.8 A charger, for example).

LiFePO4 chemistry is quite a bit different than standard li-ion, being more resilient and tolerating overcharge (within certain limits, of course). A LiFePO4 series pack can also be balanced by charging it at a low C-rate, I know this due to self-experience.

I am interested in 1. Please put me on the list!

Ah, I can totally accept that statement :slight_smile: . Balancing is crucial with “standard” li-ion chemistries and Barkuti already covered the differences with LiFePO4.

Without evidence, I won’t accept a claim that a single cell will provide more capacity if “conditioned” somehow differently than a standard, safe charge profile to an identical termination voltage and current. I’m open to examining such evidence, though.

If one charger reliably produces more cell capacity than another, then it must have a different charge profile and/or termination point.

Interested!

Please put me down for 1 unit.

Thanks…

-dmm

Interested in one.

I’ll never charge past 4.2V if I have a choice.

Regarding a charger improving performance: I don’t know much about any sort of “reconditioning” for LiIon. I know it works to some degree with NiMh/NiCd (have done it myself hundreds of times on many different cell types…). Other than that, you just want proper charge voltage and termination - and balance, if packs are being used.