should I buy a hobby charger?

I did but I can t seem to find much info on it, not like 608 on the rc forum.

From the op:

“My budget is around $50 but I wouldn’t mind paying more (even double that) if it’s really worth it.”

I suggest you get a hobby charger (for charging six or more cells as you mentioned, individual cell analyzing, 4.30v and some lead-acid batteries, etc.)
however, this thing can only charge/discharge, in parallel or series more than one cell but of the same capacity always and Mode, which is not optimum for salvaged cells. (major disadvantage of a hobby charger: you can only analyze one cell at any given time)

AND

an Opus BT-C3100 v2.2 (for analyzing salvaged cells 4 at a time without the hassle of cables and holders, charge up 4.35v, do almost everything the hobby charger can do but can do this in any combination of modes(charge/discharge/refresh) and/or cell chemistries at the same time, etc. with individual read-out for each bay.

These two can be had for less than $100…

I have both and couldn’t be more happy. I used to scour around for laptop batts all over town too.

That’s what I was planning to do cheers.

How important is Ri measurement for determening a cells’ quality?

It’s a nice feature for salvaged cells, of which a majority of them has undergone a long, hard life and would surely have high ir values already. This can be very helpful to salvaged cells for though some of them might charge near 4.2v volts, it cannot tell you the real health of the cell until you try it in high-drain lights (it cannot sustain prolonged turbo mode, sometimes jumping down in mode in less than a minute to the next lower mode , this happens from cells with high Ir)

Edit: After re-reading your op and your succeeding posts, and perhaps the joy of analyzing salvaged cells are your more important concern, a hobby charger has indeed very little appeal because it can only analyze cells singly thereby very time-consuming. (I have gone through this route before)

Perhaps getting two analyzing chargers like the Opus has the better suitability to your needs (plus the added feature of no more wires to connect, no battery cases to buy or fabricate, analyze up to 8 cells at once, etc., etc., though it was a great experience having gone through it all)

Thanks for the tip but after reading the test on the opus I m not convinced. Tbh i don’t understand it all to wel but i don’t like the current spikes it takes from the ps. And at $40 i would expect something better. If i would cash out €80 for 2 i think I would be better off going for the mc3000 instead and take my time for testing. But now I m thinking a hobby charger for charging and an opus or liitokala for discharge testing multiple cells at a time. But as I understand it the lii doesn’t do discharge test, it gives capacity after recharge or did I mis something.
Edit: keep in mind that I ll hook em up to a 12v batt most of the time and I don’t know how they will handle the current spikes. These are NOT car batteries which can handle a high initial current draw.

That current spikes was only present in the earliest version of the v2.0.

The 2.0 version had initially inflated ‘Charge’ figures (not in the more important Discharge figures), and was initially ‘cured’ by a higher amperage ps, but a resistor was added to the succeeding versions (middle production run of the 2.0, then the 2.1, that even with the same 12v, 3A since the beginning, good accuracy was attained, up to now with the 2.2 version.

And by the way, I also have the MC3000.

” But as I understand it the lii doesn’t do discharge test, it gives capacity after recharge or did I mis something.”
The Liitokala Lii_500 engineer has 2 capacity tests “Fast” & “NOR” (normal).
In “NOR” mode it fully charges the cell, fully discharges it measuring capacity then fully recharges the cell.
In “FAST” mode it discharges the cell then charges it measuring the ma required to fully charge the cell as the capacity.
The “NOR” test is more accurate than the “FAST” test as the “NOR” test is measuring the ma the cell can discharge from fully charged where as the “FAST” test is measuring the ma the cell takes to become fully charged which will be more than the actual ma the cell can discharge.
I have several analysing chargers for cylindrical Li-ions including the Lii-500 & Opus & the Lii-500 is my preferred charger.

I have found a far more useful “Internal resistance” test for me to be very simple.

I have a load (in my case an old dust buster that pulls a hefty amount of current). I then put the cells in my cell holders with built in volt meter and connect them to the load.

I watch the voltage and then sort them according to how much voltage they are able to maintain under load. This applies very well to flashlight use.

For example a 30Q might hold 3.5V and HE2 3.6v and a GA something like 3.3v.

Most salvaged cells end up in the 2.6-2.8V range with a few getting close to 3V and a lot under 2.6V (where the volt meter doesn’t work anymore.

Anything over 2.6V I keep around, over 2.8V I put into regular use as long as they do not get warm when charging or self-discharge.

Under 2.6V goes into my “wait and see box”. They all go in fully charged (already tossed the one that got hot during charging). After say 6 months any that are still holding a good charge with minimal self discharge get saved for low drain projects, all the ones that self discharged significantly get recycled.

I have ended up with something like a 10-15% success rate for usable cells, 20% low drain reserve cells and the rest are bad in my experience. Overall if you have to pay much at all for used battery packs, it is best to pass. Now new old stock is great on the other hand.

Now I have been waiting to get a constant load source so I can test the cells a bit more precisely but have not had the funds to get one.

Yes, I do this too, but instead of the cell holders with a volt meter, I use my Zebralight SC600, put in Turbo mode. This light, with a ‘healthy’ cell will go on Turbo for exactly 5 minutes then steps down to High.

Tired cells (meaning high ir) steps down the Zebralight a lot less than 5 minutes, really tired cells just for seconds.

That works too, I am just too impatient to wait 5 minutes for each cell test, I prefer 5 second per cell lol.

Course things are a bit different when you have ~100+ cells to sort through at a time vs 10.

Your way is a lot less time consuming, I should say…never got to think about it before…but after I got my iCharger, and, after Li-ion cells got a lot cheaper, I never bothered with the salvaged cells anymore.

Do u get the capacity measurement after the discharge or do u have to wait until the cells are fully charged again? Point beeing that I charge like say 6 or 8 cells with hobby charger do a norm test on the lii but cut it short when I get the read out and pop in the the other 4 cells to test capacity and rechargr the just tested cells again with the hobby charger.

Is the capacity which a cell can hold in direct correlation with the Ri or are the 2 independent of eachother. Point beeing if I know the Ri is still low enough I would have no need to know the exact capacity a cell can hold and I could go TAs way, then I would have no need for capacity test.

You get the capacity figure as soon as the discharge has finished so yes you could pull the cells then & charge them up in something else & IR is shown during the test anyway, both in the charge & discharge cycles.
Yes generally a cell with high IR will not have good capacity.
The Lii-500 also shows IR when you are just charging a cell (not in capacity test mode) so you know the IR of a cell from normal charging.
You can get the Lii-500 for around $20-$25 sometimes as low as $15 when a deal is on so you could buy 2 :+1:
I really like them (I have 2 plus 8 of their smaller non analysing chargers 6 x Lii-100 & 2 x Lii-202) & prefer them to my Opus & MiBOXER C4 analysing chargers & also prefer them to my pair of Nitecore D4”s.

To test IR cheap meters are rubbish. I use a Hioki 3554, takes a second a cell and the meter is calibrated UKAS standards.

Readings are auto recorded and you can trend cells which is at least as important as the single reading itself.

But that Hioki 3554, although obviously very accurate, is about £2,000 isn”t it ($2,500).
The OP said “My budget is around $50 but I wouldn’t mind paying more (even double that) if it’s really worth it”

Yeah right 900 + to test a few salvaged celss rofl. Then what s the point in salvaging cells. I hope for your sake u use it in a prof setting. Thx for the input though

It was an example of not using a cheap meter, they are not consistent. I don’t use it commercially but I know people who do so I aquired it cheap, they would use cheaper meters if any were avalible that were any good.

The discharge test TA uses is probably better than any cheap IR meters.

Hey man I m sorry, I see now that my post is a bit condesending if that s the right word

My Hobby Charger recommendations:

or

or
Only 50 Watt!!

http://www.skyrc.com/index.php?route=product/product&product_id=200
or
50 watt

80 watt

I use 1S4P Unprotected 18650 cell holders wired up so I can Balance charge my cells (Parallel Connected).
http://www.ebay.com/itm/2-PCS-4-x-18650-Li-ion-Battery-Clip-Holder-Case-Box-8-Pin-Contact-/121457151980?\_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140813130114%26meid%3Db99cc93b5ae4429aa220eb2f73f042d0%26pid%3D100262%26rk%3D1%26rkt%3D4%26mehot%3Dpp%26sd%3D121457151980%26clkid%3D4942104528337088887&\_trksid=p2047675.l2557&\_qi=RTM2067267&nma=true&si=q3O03D51sYJG8Zr2ntSU%252BzYPqOA%253D&orig_cvip=true&rt=nc

Wiring Harnesses I use:
For Balance port: I use the 4S one so I can Balance charge.

It is also very important to store the cells at the recommended OEM Storage Voltage. For most it is 3.8vdc.
I use this to discharge mine. Simple and works great.

I rig up 18650 cell holders in order to accomplish it.

You will also need a good DC power supply for it capable of an Input voltage: 11~28V DC for the 300 watt Reaktor. I set my up at 13.8vdc. Don’t forget you need one that can supply the amperage required as well.
I use a Server Power Supply I converted for it.
Lot’s of info here:
https://www.rcgroups.com/forums/showthread….-Power-Supplies

http://www.tjinguytech.com/my-projects/server-ps
Some for sale already converted:

Some good reading here on Hobby Chargers and Server Power Supplies.

Bill

For most hobby chargers you can salvage old laptop PSUs