Wireless Charging

Cool! So the 300 mA rated output is pretty close to the actual…also means the battery charger is relatively efficient. Mine were delivered today :smiling_imp:

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this is true, but…

charging for a li-ion is not as clear cut as it appears.
the main bulk of the charging is at a higher mA and drops slowly down to about 50mA the closer it gets to fully charged.
the chip in the charging board will monitor the voltage of the battery as well as the resistance.
as the resistance drops and voltage goes above a certain threshold then the charger starts to slow the rate of charge in order to maximise the the total charge to the battery.

my calculations are technically not that accurate as they only give the mean value of the mA charge rate.
we could assume that the majority of the charge is above 300mA until the voltage of the battery hits its target voltage.
i did do some testing of the voltage of the battery at points in the charge cycle and found the charge rate seemed to slow down after 4v (although not a great deal) but from 4.0 - 4.2v took an hour.
i assume this is when the mA started to drop… but i am only assuming.

i hope they work in your hilt design.
will you be doing a test to see how long it takes to charge a battery with aluminium in between the TX and RX coils?

Ohm’s law:

I = V / R

V in this case is charger voltage - battery voltage.
R is relatively constant, and mostly depends on the chemistry of your battery.

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I’ve been reading, and I got two different ideas for minimizing the aesthetic impact:

  1. IF you could wrap the charging coil around the hilt, any hilt with rubber or leather wraps could be retrofitted. It would still need a custom stand, probably a vertical one where the charging ring goes around the hilt. If it is close to the base, it would actually look like a vertical stand, so no problem.
  2. As some phone manufacturers do, you could put the charging coil above the pommel’s aluminum and then paint it with some thick paint/resin. In principle it would look hard to do for an amateur, but maybe TCSS could implement a specific insert of their modular pommels, and many manufacturers do use a sort of bottom lid in the pommel that just covers the speaker holes. So you could implements just that in plastic.

As a side note, I am designing a saber, but I don’t think it’s compatible with this because is an all aluminum design with a spiky pommel.

How about charging through the speaker coil?
Not sure what frequency charging happens, but I suspect it’s above hearing range…

From my experience, the colis heat up when using a tp4056 once the battery is full. They’d very hot in my tricorders.

I had to switch to Adafruit powerboost chargers, they cut things off so the coils stop heating up when full.

Does your battery have a protection circuit? I’m inclined to do some experiments, but can’t procure the same parts exactly. I have to play with whatever I can source locally.

I have an idea that may add to the wireless charging conversation:

I recently came across an old thread talking about using a blade plug charger to charge your saber battery. The plug in the thread was essentially a clear tube with a charging port built into it that could be plugged into the blade port to act as a charger. This was intended for older style sabers that used plugs to attach the blade rather than the more modern Pogo pins and contact point PCBs that are commonly used today, so not directly useful, but it got me thinking.

I realized that there would be PLENTY of space to put an induction coil inside of a blade plug , but that it would probably be a bad idea to connect a power source to the positive and negative of the blade connector PCB since the negative would go through the Proffie board (profezzorn correct me if I’m wrong there, I’m still a newb when it comes to electricity and circuit boards).

So the standard Pogo/PCB blade connector has 3 poles; Negative to Proffie, positive to battery and data line. However the “ShtokCustomWorx Battery and Speaker PCB Connector” has four poles; one for main positive, one for main negative one for speaker positive, one for speaker negative.

Both have an OD of 17.5mm so the Battery/Speaker PCB can be used as a blade connector.

That means you could used the four poles of the Shtok PCB for Positive to Battery, Negative to Proffie, one speaker pole for blade data and one speaker pole for negative to battery. That would allow charging to the battery through the blade connect; From what I have read a single pogo connector has a capacity of around 2amps, so as long as you keep the charging current under that amperage it should all work pretty well (you will also need a charging board, but that’s a given). As an added bonus the Positive and negative poles for the board both have 5 pogo pins rather than the normal 4, so potentially a higher AMP capacity for the blade.

The Bad: Doing a VERY basic layover of the the basic blade connector and the Battery/speaker connector, it looks like the two wouldn’t be compatible with one another, so you would (Likely) have to convert all your blades to the Battery/speaker connectors if you wanted to go this route.

Ok, you’re wrong.

Connecting power to the +/- of the power connector is fine, and it’s a perfectly reasonable way to charge the saber, as long as your charger doesn’t try to go over 5 volts. (Most stick to 4.2 volts, but some high-speed chargers might try higher voltages.)

You can charge directly through a 3-pin pogo connector, the only caveat is that the blade has to be powered by the proffieboard, or it won’t work properly. This can be accomplished by using blade ID to make the board recognize the charging blade plug and have it use a special preset that is always on for charging.

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I’m very interested in this concept. When you mean that it could be done, it means if the Proffie was programmed to do so, but clearly not with a V2.2?

Charging through the board FETs should work with all proffieboards and teensysabers. ProffieOS just has to keep the FETs ON, one way or another.

FETs are bidirectional, they don’t really care if the power is going in or out.

In fact, some charging may work even if the board is off, because the FETs we use have a diode in them that lets power through backwards even if the FET is off, but in that case there is a 0.4-0.6 volt drop, so the input voltage should be about 4.6-4.7 volts or so, and the charger may become confused, because measuring the state of the battery won’t work since the FETs are off.

Charging through the USB connector is an entirely different matter of course. For that you need a V3 or an addon board.

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Let me see if I understood correctly, doing NPXL connector charging is as simple as leaving the FET on and connecting to a Lithium battery charger, right?
But what we were experimenting on this thread was using a wireless connection to feed a TP4805 board that would charge the battery itself.
Have I understood the concept? Because the beauty of the latter is that any 5V source (or 9V, depending on wireless connection) could feed the stand, but for NPXL you’d need an actual Lithium battery charger.

Nothing wrong with wireless charging, I’m just saying that if you’re making a blade plug for charging, there may be an easier way.

Im not sure what the TP4805 board is, I searched the the thread and did a google search and Im not finding anything. Is that a battery charging module? Do you mean the TC4056?

If you are charging via the NPXL blade connector (not wirelessly) you would still need a battery charging module, or you could use an actual Li-Ion charger connected to the blade plug I guess. Basically a battery charger is just a power supply and a battery charging module, so using a 5V power supply and a TC4056 is just making your own battery charger. The wireless charging board just means that you can transmit the power from the power supply to the charging module over a short distance.

If you made a blade plug specifically for the purpose of recharging, you could put a wireless charging module in it very easily. You could also put a charging port in it if you wanted, but that may make things complicated with the above motioned induction heating of metal components.

While making a separate device to put into your saber in order to do wireless charging does seem a bit contrary to the objective, it could be a good solution for people that have replica sabers that don’t have an easy means to connect a charger without removing the chassis (me) and could still be a good way to make a charging base that doesn’t connect to the saber with wires and looks more “in world”.

I’m mostly just playing with options right now and trying to keep it in the subject of wireless charging.

Yes, totally fudge the numbers. Sorry. Should have looked it up first.

Regarding the other part, all seem very valid options. As Fredrik and you said, you can use a custom bladeplug today to charge them. I love your idea of using a wireless bladeplug, with an integrated TC4056.
I wanted pommel or handle charging for aesthetic reasons, since I could make vertical stands and the charging would be absolutely hidden. Using a bladeplug would not be so aesthetic, but could very well be accommodated on an horizontal stand.
In fact, now that you mention it, by going not wireless you could make wall stand where you plug the hilts to the wall baldeplug and just secure it with the standard slug. That’s a very interesting idea, in fact, while not wireless.

My saber is pretty basic and is a replica, so I am extremely limited on things like external ports and the longer I own it the less I want to remove the chassis. I also have not had much luck with the removable speaker options , so there aren’t many good options for that end of the saber since the 28mm speaker takes up ALL the available internal space. Being able to charge from the blade end opens up some interesting possibilities.

If so, I think that if you wire a 5V source to a TC4056 inside the plug, and its output lines are connected to the GND and P rings, if should work. In fact, and I guess Fredrick understands this better than me, if you put a (100k-20k ohm) resistor between GND and Data (in the plug), you can actually identify the charger as such. I wonder if some special style could be made for charging.

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That resistor should be identifiable with blade ID, and then you can have separate blade defintions and/or presets for it.

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Any recommendation for such a preset. Like set to black so the FETs are turned on but no power is applied?

Black will actually turn the blade off, try StylePtr<Rgb16<1,1,1>>().

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