SkyRC — IFA 2014 — MC3000 charger-analyzer

[Gauss163]

@kreisl A "Dream Charger" should not require kludges such as Post-it notes. Rather, it should exploit existing technology to the hilt, e.g. automating what can easily be automated, so to better make the machine as foolproof as possible. This charger has some minor, incremental improvements over others. But it is very far from making the big design leaps needed to earn the name "Dream Charger".

 

[Curetia]

Hi, the 2nd difference i was referring to is the quality of the metal contacts/sliders. The production parts are "silver-plated" for better electrical contact or conductivity, an improvement. Can anyone see on the pic that the color of the metal parts differs between the two charger units?

I can see it, but i didnt think, that this was the difference. I thought it is difference because of the light.
I hope I can buy this charger soon

 

[Ferdinando]

Kreisl, so the idea to have the charger with two operational modes:

'automatic'
it starts charge upon cell insertion with no manual key press
it starts charge automatically only Ni-Mh and Li-Ion
(or what you want, it just an example)
choosing the type by reading the voltage of inserted cell

for other chemistries, the user must choose the right program from library, using keys

'manual'
it can charge all supported cells with usual key-press

is not applicable ?
it does not solve the security problems ?

 

[dts71]

I just found this thread - it seems there will be a new charger for Christmas.
I'm super excited

 

[kreisl]

it starts charge automatically only Ni-Mh and Li-Ion
(or what you want, it just an example)
choosing the type by reading the voltage of inserted cell

Hello Ferdinando, so far the charger has UI Mode: Advanced and UI Mode: Simple, both are 'manual' UI modes. I dig your idea. I mean.. limiting the number of automatic rechargeable battery chemistries to 2 only at a time. The user would have to make the selection beforehand in SETUP; once set, the user could charge his/her preferred 2 chemistries without pressing any key.

Following KISS and editor's choice, less popular or dangerous chemistries would be unavailable in the selections: NiZn, RAM, LiIo435. Also NiCd and Eneloop because their charging algorithm could be covered by NiMH. In other words, people who really need to charge these 5 chemistries explicitly would be forced to work with either of the two 'manual' UI modes.

What's left would be: NiMH, LiIon, and LiFe. Since the voltage ranges of Li-Ion and LiFePO4 overlap, there is imo no acceptable way that a smart charger could safely distinguish between these two Lithium-based rechargeable chemistries. That's why Xstar VP2, Nietcore D4, Opus BT-C3100, a.o. have a Li-chemistry selector switch — with such a 'smart' charger the user must still be aware of the switch setting!

So the selections in SETUP would be:
123456789012345678
UI Mode: Simple
UI Mode: Advanced
UI Mode: NiMH/LiIo
UI Mode: NiMH/LiFe

Apparently, NiMH/LiIo and NiMH/LiFe would be our 'smart' (or 'automatic') modes, and the user would still be prompted to enter the charge rate or else the charger would proceed with the displayed default rate. KISS again, the default rates would be fixed in the firmware and could not be changed by the user.

What do you guys think, do you like it:kiss:?

 

[Gauss163]

there is imo no acceptable way that a smart charger could safely distinguish between these two Lithium-based rechargeable chemistries.

But there is. As I described above, there are intelligent ways to recognize individual cells, e.g. by using a bar code reader either on the charger or on some device (e.g. cellphone) that the charger can communicate with.

 

[Gauss163]

@kreisl Since you are in contact with the developers, perhaps you can answer this question. Has there been any safety analysis done on the charger? If components fail can it possibly lead to dangerous situations?

 

[kreisl]

if critical states are reached as a result of some unknown cause (like component failure), the system will issue a warning song and usually shut down soon after, depending on the situation. there are hardware components and firmware components which take care of abnormal situations. and if certain components malfunction, an error code would be issued on the LCD. those codes are not documented in the user manual, they're reserved for internal use only, sorry. safety has been tested on their own terms ('analysis').

all good! :thumbsup:

 

[psychbeat]

It's a novel idea but personally I don't want to print barcodes & stick them on all of my cells.
I'm also fine with pushing a couple of buttons but it would be nice if I could keep a slot in the last setting I had it in or have a preset for it that I could easily get to.
I'd mostly be doing 2 amps Li-Ion but have a few smaller cells and some eneloops.
Might get some 4.35s eventually after I get this charger

Anyways, I'm not hung up on just sticking any cell in there & letting it figure out what it is for me since that seems impractical + this is an "advanced user" piece of equipment.

 

[Gauss163]

@psychbeat Sure, for some users (e.g. those with few cells), the extra work involved in labelling them may be more trouble than it is worth. But for those with many cells, and for those who are interested in tracking their health, it could prove quite convenient. The more you can automate these processes the easier it is to coax users into contributing stats to community databases. The knowledge gleaned from such field-testing could prove immensely useful. In fact it could prove more useful than the limited tests done by manufacturers.

To me, a Dream Charger should have enough configurability that it can be optimized for most every class of user. But that may be asking too much at certain price points. Whether or not that is true here we cannot say, since we have no idea yet what the price will be.

 

[Gauss163]

@Kreisl I cannot determine much about safety from those vague words. Do you actually have specific knowledge of what (if any) safety testing was performed? It would be very interesting to learn how Chinese charger designers typically address safety (if at all). For example, do you know if they employ industry standard methods, e.g. failure tree analysis or FMEA (failure mode and effects analysis)?

I suspect that for consumer-grade chargers they do not perform proper safety testing. But I would loved to be proved wrong in some specific case.

Some further discussion on safety matters can be found in prior threads, see esp. here and here.

 

[kreisl]

it would be nice if I could keep a slot in the last setting I had it in or have a preset for it that I could easily get to.

last program/slot memory. The charger memorizes the last used program number (per slot) between power off/on's. And if you want to copy this program over to all other slots with a single click, no problem. The "a preset for it" is exactly this: a specific program number, say [13]. You can keep [13] assigned to #4 (=slot4), also no problem. The glossary in the user manual clarifies on the concept or difference(?) of 'what is a program number?':

Program number = a program number is the program with this number, and not only the number itself

Maybe the above definition sounds trivial, banal, silly logical but give it a moment to sink in. In other words, in the context of this charger, program number is synonymous with program, and vice versa, because in practice they mean the same, there is no practical difference between the two, either cannot exist on its own independently without the other, they are inherently tied to each other.

Gauss163, sorry no further details provided, i am satisfied with my given answer, moving on

 

[Gauss163]

@kreisl Sorry to hear that you do not have any solid details about any safety analysis. It would have been interesting to find out what methodology is (typically) employed by Chinese firms. Given the prior track record, probably the answer is "little if any", which should give one pause.

 

[alternety]

Just a small note to get my wack at the horse. Given how picky some devices are about cell diameter, I am not sure the idea of sticking on a bar cod label on a cell is a generally good idea. Now, printed on the wrap by manufacturer would be neat. Manufacturer ID, Cell size, type/chemistry, capacity, serial number, etc. The bar code could get a bit long.

Someone could start a project to build a printer capable of doing indelible printing on the cylindrical sides of multiple diameter cells. Or strip off the sleeve, print your own sleeve, shrink it on.

Then the scanning. A moving scanner bar under each cell position would be pretty expensive and take up some space needed for other things. Build the charger like an artillery piece. One tube to each charging station, a ram rod to push the properly rotated cell in past a reader, and become the negative contact.

Or allow the charger to accept external data and commands and use a stand alone simple scanner. Push button to specify position it will go in and scan.

It would be useful to people with lots of batteries (or maybe just a few but are more anal retentive). By serializing you could attach a usb port or something and collect data by cell and keep a data base, plot recharge capacity over uses, etc. Certainly easier that using a sharpie to ID each cell and keep manual database updates.

Cell size would make this a bit tricky if you have a wide range of really small ones.

There are some details to work out, but it would be nice.

 

[Gauss163]

@alternety Devising a good way to label cells should not be difficult, e.g. one could print onto a very thin tape such as Kapton. There are myriad possibilities. That's not my area of expertise. The next time I'm at MIT I'll prod some of my former classmates who work in related areas to see what they recommend.

 

[alternety]

OK. You do realize I was mostly being silly?

As I said, a very useful feature if it can be implemented at reasonable cost.

 

[Dubois]

..... That's not my area of expertise. ....

Wow, something outside your area of expertise.

 

[Gauss163]

@alternety Of course, I chuckled at the latter half. But the concerns about thickness may well be valid in some contexts, so I thought it worthwhile to address that. @Dubois Alas, too much! If only there were more hours in a day...

 

[alternety]

I wonder if an RFID patch could be used. I don't know how thin they are or how well they work on a metal surface.

 

[Julian Holtz]

Apparently, NiMH/LiIo and NiMH/LiFe would be our 'smart' (or 'automatic') modes, and the user would still be prompted to enter the charge rate or else the charger would proceed with the displayed default rate.

I think that most users only have NiMh and LiIon cells. So an automatic solution that works for them would already be a good thing. This means, a fully automatic mode is available as soon as all enabled cell chemistries do not overlap voltage-wise.

This means you can choose Nixx or NiZn, and choose either LiIon or LiFe. All available cell chemistry types must be clearly distinguishable by the charger.
If you enable more types, automatic mode is not available for the similar cell types.
You could, of course, enable NiMh, NiZn, and LiIon.
Insertion of LiIon could trigger the automatic mode, but not insertion of NiMh or NiZn.
Whenever the automatic mode is triggered, the charger must not be able to have any doubt about the cell type inserted.

I think this is the best solution within the means of current technology.