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

There was no reason for the MC3000 to be so expensive in the first place except that there was nothing quite like it at the time, it was a very botched attempt though, both software and hardware.

I’m all for a better though out MC3000. :+1:

I was under the impression it had undergone a revision or two and was a lot better now... but then again, I don't have $100 for another charger... that's flashlight money!

Love it. Two of the “must have” features for me is adjustable current and adjustable termination voltage. Great for extending the life of cells.

I’d rather drop some of the fancier features if it keeps the price down. Otherwise, the SkyRC MC3000 already exists for a high price.

#1, #2, #6, #11, #13 are the most important features.

#4, #9, #10 are nice to have, and shouldn’t add to the cost.

  1. is nice, but might add the cost. Probably worth keeping if it’s not too much more expensive, though.

The rest can be dropped if it keeps the price down. Set the max current at 1A per channel, and you won’t need fans, temperature monitoring, etc. Maybe 2A if only 2 slots are used.

Oh, maybe drop LiFePO4 support if it causes safety-issues with automatic restarts, as another poster suggested. Most people probably just need NiMH and 4.2v lithium-ion support.

Regarding the price goal and the considered OEM list for this project, i don’t see how SkyRC would agree to produce a better charger than the MC3000 for a lower price.

Really great idea here BlueSwordM

I have been using the Charger Xtar SV2 Rocket Rapid Battery Charger for a couple of years now and really like it.
I would like to see something similar but with battery voltage display instead of the battery % charged display.

Or all of the above with 4 channel.

J

Oh boy that’s a long thread.

I’ll have to respond to all of the ideas here.

Agro first:

- 50mA minimum charging current. Ok then. However, 50mA-100mA-100mA+100nmA will have to do.

- 2 larger outer slots would work, but it would require a more custom design. Not more expensive. Just takes more time.

- Capacity measurements will start at 100mA, right up until 700mA. Rather than using resistors, we’ll maybe be using linear fed MOSFETs for discharge. 1A would be doable, but the fan would have to be very good, or use a 90mm internal fan/120mm external fan.
Higher is not possible.

- Good idea, but something I do not want. Good 4,20V terminal charging would be best.

  • USD PD input would be very nice, but more expensive than a 5,5*2,5mm DC input jack.

@KevinZA1988, as I said with Agro, would be good. But would make the charger larger, and require a stand to work well. Costs are a bit limited here, so… maybe.

@Lux-Perpetua, storage mode is already included in the list.
Sudden off protection like on a PC can easily be done, and the charger wouldn’t come on until you press a button.

@Grigio, how about a color LCD display to the likes that RD Tech uses? That would be nice.

@delete, unfortunately, that would be too low with the kind of features we want.
A simple 18650/21700 8A charger could be doable without all the added features, but keep the most important ones, like a large current range and charging voltage selection.

@AEDe, thanks for the suggestion for Folomov. Will try to be careful with them if we decide to choose them.
About that non-standard battery charging. We could go include nickel plated neodymium magnet connectors to charge other devices.

@tempo, I’d rather say 49$US for a complete charger.
Powerbank functionality? Yes, but limited to a max of 900mA per the USB 3.0 spec.
USB-C PD input? No for cost reasons.
USB-A output/USB-C output for data? Yes of course.
USB-C input for updates? Yes.
WiFi or Bluetooth? Yeah no…

@varbos, increased the length to 80mm instead of 78mm.

@1332332331, microSD it is.

@hasddie293, this is what I’m implementing a full charge cutoff at 4,2V. Doesn’t charge back up until 4,0V.
For voltage cut off, something like a large capacitor would help.
No C-Rate functionality.
USB-A output at 5V 900mA, or maybe 5V 1,75A.
Good accuracy is important.

@WalkIntoTheLight, absolutely.

Should be good as long as the software is done by someone who knows what they are doing & if updateable it is easily done , I hate buying stuff that is inferior to the updated version that comes out a month later but don’t want to buy again to get the updated version.

Some random outsider thoughts. Most have probably been covered by others, and the rest impractical:

- Bluetooth is a nice whiz-bang feature, and a way to get a lot of info to display all at once via a phone app, but I don’t see it as essential Very Nice, but not essential.

- Adjustable charge rate and cutoff voltages - maybe based on a few canned profiles and x number of custom profile slots. Make sure the user defined profiles are hard to save/overwrite. Definitely do not autosave the settings when backing out or going to a new profile.

- Positive Action required to start a charge / discharge action (no automatic start by default)

- USB output/charge port - connected to either 1 slot or smart slot selection combining by cell voltage

- Input power - standard barrel connector or, preferably, a USB C PD port. (too bad POE is high voltage and low wattage - can you imagine plugging your charger up to a network port and controlling it from any web browser on your subnet?)

- Command port to connect to a PC via USB for control, reporting and updates - maybe make it emulate a network connection so the command interface can be browser based?

- Recording activities to an onboard SD sounds nice, but how can you match up a log entry to a particular physical cell after the fact?

- case color - why not. Original iMac colors? A nice clear, smoke, or frosted semi-transparent? This would make activity LEDs easy to place by each slot.

- Accurate mAh and internal resistance measures are a requirement

- Display - Color is a Nice To Have, but a large, clear display that shows all pertinent info for each cell (at the same time) is required. Maybe put in a mid sized phone type touchscreen color display and do away with most of the physical buttons too?

- UI - I don’t have experience with anything other than my Zanflare C4, but here it goes… Keep the one button under each slot. Make them a slot selector instead of a slot display cycle. Have it set so you can click one to select it, but if you hold down on it, you can click other slot buttons for a multi-select. Two control buttons. Use one to select the mode / data item for each selected slot, the other to modify the values for the selected mode/data item for the selected slots. I’m not sure if the Start function should be a selectable mode/option under the first button and enabled by the second button, or a separate, dayglo red warning sign recessed into the case so you can’t accidentally press it.

- Long Cell Support - Heck Yeah!

- Storage Charge mode - set the desired voltage and it will charge / discharge to that point then disconnect the slot

  • incorporate an Android controller — while this is a nice feature, I’m not all that comfortable with it. It would allow for a rich application control and upgrade path, and a nice UI if paired with a color touchscreen, but I know someone will insist that it have a wifi connection and it will become yet another IOT device waiting to be exploited. Then there comes the cost…

1. Any wireless protocol will not be included for cost and reliability reasons. A direct USB connection to a PC would be best.
2. Yes, that would be good.
3. That would be good, but I’m lazy. :slight_smile:
4. Highest cell voltage/internal resistance USB connection.
5. Standard 5,5*2,5mm DC jack input.
6. Yes.
7. Oh that’s easy. Until the charger is completely off, every charge cycle will go like this:
Cell 1-2-3-4
Cell 5-6-7-8, and so on.
8. microSD card functionality would be good for automation, but USB data output is still better, I agree.
9. Case color options would go like this: Black and white.
10. Display. Large IPS display it is.
11. Good UI.

Everything else has already been said, but no Android functionality is to be included for the reasons you mentioned.

With every feature included here, 49$US GB should be doable.

Interested but if possible not with MiBoxer which tends to sale on amazon with coupon for amazon US most of the time, they don’t care about the rest of the world.

Which is why I’m planning to do a GB with someone we know and love, Neal!

Or maybe Banggood.

@tempo, nice find!

I hadn’t thought about the OEM behind Liitokala chargers.

MiBoxer would also be a nice bet as I’ve said before.

A C4-12 BLF edition would be nice, yes?

I’ve limped along with an aging Nitecore Intellicharger and have had to wrestle longer cells into the slots. Keeping my 26650 cells in the slots and touching the terminals has been a delicate operation. It’s like I need the dexterity of a safe cracker to keep them in contact. It doesn’t charge some of the LiFePO4 cells I have and the flashing leds only give me an estimate about how charged the cells are at any one time.

Still, I’ve hung onto it and have waited for a reasonably priced, quality charger with an easy to operate setup. Just like my lights with Narsil and Andruil, I like the flexibility, but I can operate it easily without thinking. I hope that in the rush to get a “pie in the sky” charger, it is easy to use.

I’m glad this thread was started. I’ll keep a close eye on it for the future.

YES! YES! YES!

The perfect BLF charger is much needed.

I am very excited and in for at least 2 when the time comes.

BlueSwordM, this is a great idea, and, as a charger-aholic, I’m in for certain, regardless of cost. To me, some important criteria, which have only been mentioned in passing so far, are: quality, precision, and accuracy. Unlike a fun, hotrod flashlight, a charger serves only as a tool, not a toy. No one is going to start modding chargers as a hobby, so it needs to be good out of the box.

The object, I think, is a reliable charger that charges accurately at the desired rate, terminates accurately at the desired level, and does so in the desired amount of time. I think an automatic muggle mode will be fine for many people. But there are tradeoffs between current, voltage, time, and battery longevity, and I want to be able to determine the tradeoffs myself. This is what makes the MC3000 such a great charger, in spite of its convoluted user interface. Charge termination for NiMH batteries is an example of an area where most chargers are both woefully imprecise and inflexible, as you can see from HKJ’s reviews.

Speaking of which, you might want to see if you can involve HKJ, and also Kreisl, who helped develop the MC3000 with SkyRC.

Let’s do it!

@CLB, I already thought about HKJ, but we don’t need him and others, yet.

I’m currently collecting features and ideas.

I know it may cost more, but what about making the base/casing out of aluminum with built-in heat sink fins?

I understand, BlueSwordM. One feature request I would have is the ability to create custom programs, as with the MC3000. This has turned out to be the most important feature of that charger, for me. It saves a lot of time, of course, but, even more important, I don’t have to remember all the various settings for different cells and functions. I have a chart which shows the settings for each program, sorted by cell type and size, so all I have to do is look at the chart and punch in the program number. Once set up, the MC3000 actually became the easiest to use of all my dozen analyzing chargers.

For the love of god, no.

My understanding is also that kreisl has been banned from BLF years ago.

Interesting. :slight_smile:
Whatever allows improved performance while maintaining low (no?) noise is interesting and I would be glad to pay extra for that. :wink: