PC charging app?

AngryBob

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I know I can charge various devices, or a single cell, from the USB port on a PC.

Does there exist any app which gives detailed info, or any info at all, on the state or progress of the charge?

Or perhaps an intermediate piece of hardware, which is inexpensive enough to be both useful and reasonable?

I know there are fairly high-end chargers which do interface with a PC, mostly just using a larger display. These are also out of my price range.
 
The kind of cells that can get charged up in a reasonable time period from the power a USB port puts out is **very** limited.

Chargers that put out more power and do a good job can cost a fair bit. The ability to have the charge process monitored on a PC does not add much to the cost, but is less common.

Yes there are devices that can go between different chargers and the target battery, and output data to the PC.

The app part is usually free, but quality hardware is not.

So, let's start with what exact batteries you want to charge, and how long you're willing to wait if/when you are in a hurry.
 
I'm going to make another post on this, but I am acquiring a quantity of used, but hi-grade tool packs. Bosh, Hitachi, Milwaukee, Dewalt.

Cells appear to be in parallel pairs, or at least I think I should keep them that way, so two at a time for starters. My thought was a USB cable, old laptop, and some software might give me some useful information.

I know there are issues with recycled cells, but this is partly for a learning experience, and a useful pack will be something of a bonus. CTF, cheap to free, is a major concern right now.

Otherwise, what would be a decent, CTF, wall-wart type charger for small groups of cells? Old cell phone charger? I have a vape charger for two cells at a time seperately, not sure if paired cells will work, one pair in each slot, I assume. Not sure how safe that would be, charging will be monitored closely.

I have quite a bit of free time, am mechanically inept, and budget is slim to none.

I have a decent idea of what needs to be done but absolutely no clue exactly what it looks like when doing it.

My son is reasonably handy and has some small interest in the possibility of an electric dirt bike, working together on such a project is maybe the most valuable outcome.
 
"USB power meter" on google and thank me later.

More info: Latest USB can deliver up to 20 volts @ 5 amps.
 
in theory, not yet implemented that I've found, 40-5W and not continuously variable but only coarse increments.
 
AngryBob said:
My thought was a USB cable, old laptop, and some software might give me some useful information
You will be spending money on things that won't be of much use later. Forget USB as a power source for now, treat it as a comms connection if you come across a charger / PSU with that ability cheap enough.

> I have a decent idea of what needs to be done but absolutely no clue exactly what it looks like when doing it

Set some concrete goals, yes money can be saved but too vague won't get you anywhere.

What voltage range do you want to get to? To power what, initially?

You definitely need a DMM and ammeter to start.

For chargers, a variable output voltage, and ability to control amps out are pretty basic requirements.

Start out with a cheap AC-to-DC power supply that puts out around 12V, 24V would be even better.

Hobby chargers and cheap-Chinese "lab style" PSUs will take the above output and let you experiment with 1S, up to say 8S charging voltages.

Maybe a $100 budget will get you started?
 
I just checked pricing on the MeanWell units, these have either come down or I was looking in the wrong place last time I checked. Do these require a seperate power supply or plug into the wall socket? I have standard PC power supplies out the wazoo, unfortunately no server supplies at this time. Threw away several before I knew they might be useful.

I do have a 10S charger for current battery but did not want to experiment with my only working charger. Part of this project is to be working with spare parts which if I activate the smoke chips is no great loss.

I also have not one, but two, voltmeters, have actually used one once and made the needle move.

Current end goal would be to have a 10S replacement for my existing 4 year old battery. Or a 12S, which would mandate a new controller to replace the current one. Any way to cover both 10 and 12 with one charger, I am guessing the voltage adjustment does not extend that far. So I have to make a decision, right? I was told existing controller will NOT do 12S. I do have a spare, though.

So it sounds like I should get a charger for full pack voltage and create series strings and charge those. BUT - I still do need to charge single or pairs of cells while testing, in order to make those series groups, so what is useful for that?

I have read DrkAngels threads on battery packs and plan to follow his methodology for capacity and self=discharge testing. Also several other similar ones. There are LOTS of steps I am not sure of the exact procedure.
 
Yes Mean Well makes great stuff

PC supplies can be fine too.

but whatever goes to the actual battery needs to be solid on current limiting, ideally fine adjustable amps rate.

Most LI is 4.2V stop-charge per cell, HV gets a bit higher, LFP is 3.6.

so the difference between 10S and 12S is 2S.

Chargers need accuracy, controllers are more forgiving.

A bulk charger for fast recharge of finished packs is one thing.

A cell-level charger for testing, balancing etc is another.

Getting one lab style adjustable PSU to to everything is expensive and rarely very portable.

Most AC powered hobby chargers aren't great but if you find super cheap say eBay give it a go, while you save up for good stuff.

Yes, read a lot and take notes in a full text searchable tool to build up a reference knowledge base.

check out how this works https://www.google.com/search?q=site%3Awww.rcgroups.com+capacity+OR+discharge+testing

 
SFAIK, Pc power supply has 5V and 12V, and can be used to power an RC charger or Meanwell, but not as a pack charger? I already have many PC power supplies as surplus.

Most RC chargers I have seen do not go above 8S, since I will go either 10s or 12s, I did not think I could use one of these? I had also thought most of these and the Meanwells required a 12V DC supply, which means two items to purchase, though I have the above PC units to play with for free.

The only charger i have seen with an adjustment range which would handle both 10s and 12S is the Satiator, I know the Meanwells can be adjusted, but not that far, I thought? i will most likely stay at 10S, don't really need more speed and my seller was pretty clear I would need a new controller for 12S. Essentially I would like to keep options open, but I think I will need to nail down desired charging voltage before purchase.

SFAIK, I could use a 5V source to charge a 4.2 cell, but ONLY with constant and careful monitoring, and it is likely not something I should be doing. I can be careful, but not constant. Would say a cell-phone charger at 4V or similar be usable for single cell charging and testing?
 
Ebay to the rescue. 4-cell, usb powered, less than 5 bucks. I got about two dozen available usb ports. Twenty bucks does sixteen cells, likely take several hours, but time is another thing I got a good supply of.

CTF battery, here I come!
 
You can get around the RC charger size limitation by keeping your battery in units of <10S and for example using 2 harnesses, one a parallel harness for charging that keeps things low voltage and one that combines your <10S units into a pack of whatever series count you want. I like my iChargers for their flexibility.
 
AngryBob said:
SFAIK, Pc power supply has 5V and 12V, and can be used to power an RC charger or Meanwell, but not as a pack charger
Think volts and amps, not arbitrary labels.

But yes unlikely something you already have will do for your long-term goal. But maybe good enough to start your hands-on learning.

RC Hboby chargers that can do 10S or 12S are not rare, but not free, and fuggedabout Grin's stuff for now, save your pennies.

Adjustability, learning to series / parallel, going solderless pack building for now for flexibility.

2x 5S is 10S
2x 6S is 12S

12S you could series 4x 3S, that's in the 12V range, can start with that.

Yes you generally need PSUs to power the better RC chargers are DC-DC. Mean Well are PSUs not chargers, but current-limiting even better adjustable current gets you there, just need to babysit the stop-charge.

For single-cell forget USB and cellphone style you need setpoint adjustability.

if not an RC charger, go for a DC-DC buck converter with adjustable voltage and current, 3.3V +20% gets you to 4V, or 5V -20% gets you there too.

Cheap chinese lab style PSU will do as well.

 
If I got this right, a true charger, at the end of the charge, is at a constant voltage, 4.2 presumably, and the amperage gradually tapers off to near zero, or thereabouts.

It also starts at a constant amperage, while the voltage gradually rises, or so I understand.

Does the power supply not do either of these things, only one, do I have to manually adjust during the charge, in VERY SIMPLE terms, what is the difference between the two and most importantly, what bad things can happen if I do not do what I should be doing, but screw up and don't?
 
No real "true charger" definition objectively.

The most important element afaic is current-limiting. Lower-cost latching or even hiccup mode OCP interrupts the charging process, you really want the ability to transition to constant current mode,

since LI chemistries will always demand a higher amps load than what's good for them, and/or will release the magic smoke on unprotected sources.

This applies to PSUs as well as "chargers"

The key in that distinction afaic is an automated stop-charge function. Some claim to be chargers but don't even do that.

Ideally can be adjusted by the user, sometimes just a simple egg-timer, sometimes an algorithm that tries to adjust automatically, the ideal is based on tapering amps measured at the pack.

The Bulk/CC vs Absorb/CV stage transition you describe is not controlled by anything external, not by a human nor the charge source regulator, but

inherent in and controlled by the battery, varies by C-rate, SoC, chemistry resistance/CAR etc.

Some "stage" chargers drop from Absorb voltage down to a lower Float after the charge process is finished, but that is not so needed in this context.

But **adjustable** voltage setpoints, ideally user custom variable within a wide range to me is critical.

And an adjustable output current is IMO also important, even if only a few canned choices.

These last two are more commonly available in "lab style" PSUs, units marketed as "chargers" with these abilities are generally expensive.

Note all the above only applies to the unit actually connected to the battery. If you go with a hobby charger powered by a PSU, the latter can be dumb as rocks, all the smarts are in the DC-DC charger.

____
So, current limiting is essential, really a CC mode. If not adjustable then the limited output will safely charge only a certain Ah range to keep to an appropriate C-rate.

If there is no stop-charge intelligence, then you the owner needs to monitor the V/A output and pull the plug when the time comes.

Depending on the condition of the batteries, relative V / A of the source, doing any of this wrong can result in "unexpected thermal runaway events", boom bad.

So never mess around inside your living space, do it outdoors or in a back shed, maybe a suitable garage.

And never leave charging unattended.

Unless you spend a lot more money on infrastructure and go to a safer chemistry like LFP or maybe LTO, but sounds like not in your situation.


 
I appreciate the information, and even understand some of it, but.....

If I purchase and use a Meanwell, what do "I" need to do that is different from plugging in my current charger and waiting for the red light to turn green, then unplugging it?

SFAIK, I do need to open it, adjust the output voltage to match the pack, maybe also adjust the current to some value that is best for my particular pack, based on ?????, then, after that, I plug it into the pack, and then what? Other than do NOT leave the room and do NOT fall asleep?
 
This would be deal of the decade if you lived close enough to pick it up, the weight is going to make the freight expensive.

Yes literally overkill for your needs, but hey, future proof! 8-D

Sorensen DCR 600-16T DC Power Supply 0-600V/0-16A
https://www.ebay.com/itm/Sorensen-DCR-600-16T-DC-Power-Supply-0-600V-0-16A-/352723664528

 
AngryBob said:
If I purchase and use a Meanwell, what do "I" need to do that is different from plugging in my current charger and waiting for the red light to turn green, then unplugging it?
Well Mean Wells are not lab supplies, so I doubt much if any current adjustment. And the voltage adjustment might be only 10% or so, so would not be able (I think) to charge both 10S and 12S from the same unit.

The voltage tweaking will be based on your knowledge and judgment, perhapa adjusting for whether you value maximum range today over longevity, or one set of packs is getting old and dicey, charge lower for safety than your strong packs from new cells.

You will always want a trusted accurate DMM and ammeter showing V and A going into the battery so you can see when to shut down the charging cycle.

Never blindly trust charge source readings, and certainly not any blinky lights, even if accurate to start they can easily go out of whack.
 
This one I tried to snipe at $40, obviously worth a lot more but hey you never know!

https://www.ebay.com/itm/Sorensen-DCS40-25E-0-40V-0-25A-Power-Supply-/163773722918

This I went a bit higher since 60V is more useful, but also got outbid.

https://www.ebay.com/itm/SORENSEN-DCS60-18E-DC-POWER-SUPPLY-POWERS-ON-NO-OTHER-TESTS/352685434114


Patience and perseverance eventually pays off though!
 
Here's a short thread shows some of the interaction between voltages, charger types, available power etc

https://endless-sphere.com/forums/viewtopic.php?t=101364
 
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