Strangely, the 18650 seems to have a peculiar property where it gets cheaper as the capacity increases. You can get 12 Ah (12,000 mAh) cells on Ebay for less than two bucks these days.
There are plenty of videos on Youtube showing people cutting these cells open to reveal what is inside. In some cases, an itsy bitsy LiPo cell and a bunch of sand.
Ebay does nothing to stop the swindlers, even after having been notified.
-- RoRo
Wow, that's surprising. The additional ink costs something. ;-)
Believe nothing being sold on these sites. Batteries seem to be the absolute worst. It can be difficult to find honest battery suppliers. Buying directly from the manufacturers is almost impossible, even if your volumes are quite large (been there, haven't been able to do that).
Ultrafire 18650 batteries are junk. Here's the discharge curve of an allegedly 3000ma-hr Ultrafire 18650 cell at 1.3A: Looks like it's really only good for 800ma-hr capacity. You would need three or four of these cells to equal the capacity of a real
18650 cell.For fun, I crammed the blue Ultrafire 3000 cell in the photo into a handy flashlight and ran it until the light quit. No runtime number here because the battery was partly charged. I then crammed it into a XTAR VC2 charger and started the timer. The charger indicated it was charging at 500ma rate. I missed when it actually proclaimed the battery as being fully charged, but my guess(tm) is 70 minutes. The theoretical charge time at 500ma would be: 800 ma-hr / 500 ma = 1.6 hrs
One problem with over-rated and junk batteries is reconciling the discrepancy between the over-inflated capacity, and the real battery capacity. The problem is that the recommended charging rate is about
0.6C. For the Ultrafire 18650, that would be: 3000 * 0.6 = 1800 ma (using advertised capacity) or 800 * 0.6 = 480 ma (using measured capacity) If I tried charging this Ultrafire cell at 1800 ma, I would be overcharging it at 2.3C. Therefore, if you must buy junk batteries on eBay, take the time to measure the capacity and use the measured value to establish the charging rate.For more info, I suggest you dig through:
Drivel and status report: Just escaped from the hospital. Laser lithotripsy to remove one kidney stone failed. I go back in a week or so to try again. A month later, I repeat the ceremony to remove the other boulder. I'll be rather scarce in the forums and mailing lists until I'm recovered.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Hope everything goes well from now on.
-- Regards, Carl Ijames
Good luck with that one :/
NT
Yes, good health to you for new years !
First of all my sympathies.
Can I ask why the procedure failed first time?
-- Mike Perkins Video Solutions Ltd www.videosolutions.ltd.uk
Thanks, and also my thanks to others who also offered their sympathies. However, none is required. I plan to get through this mess and return to normal eventually. The trick is not about modern medicine or money. It's about surviving bad scheduling, hospital super-bugs, medical mistakes, and oddly about practicing medicine from a lawsuit inspired medical cookbook. So far they've only tried to kill me once (by accident), but most everything else is going fairly smoothly.
Laser lithotripsy. The laproscope is about 5.5mm wide. They were only able to enlarge the entry hole from the ureter to the kidney to about 3mm dia. (Note that stents are normally sized by circumference, not diameter). Any larger, and I started bleeding profusely due to my being on blood thinner (Plavix). The surgeon was unable to get the laser into the kidney. So, they left a 2mm dia stent in place to eliminate the painful backpressure, patched me up, dropped the blood thinners form my growing prescription list, released me on Thanksgiving evening, and asked me to call on Monday for round two. My best guess(tm) is the next attempt will be using PCNL: "How are Kidney Stones Treated?"
I had the same laser lithotripsy procedure 10 years ago for removing a previous boulder. It works, I recommend it, but has some limitations. The big one is that it only breaks up the boulder, and does NOT remove the debris. That took about 10 days and was Level 10 agony for the entire period. The not so big limitation is that running a laproscope through a rather sensitive part of my anatomy can be rather painful when later trying to urinate. I've repeatedly asked for some 5% lidocaine topical ointment to deaden the nerves, which has been repeatedly "forgotten". I wanted to mix my own using some illegal cocaine, but failed to find my 30 year old stash.
If you want more details, email please.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
I was speaking from experience from 2 failed laser lithotripsy and one successful, and in the mean time two rounds of SWL. This went on for months! Mine was 11mm.
I'm aware the ureter is a very sensitive and easily torn, so I can understand the reluctance to do anything to compromise the small tube.
LOL - been there and got the T-shirt!
I have heard women say the pain is as bad as childbirth.
So when I'm told about the pain of childbirth I say that I've heard from ladies it's on par with kidney stones. Naturally when they say 'have you had a child', I counter with 'have you had a kidney stone'!
-- Mike Perkins Video Solutions Ltd www.videosolutions.ltd.uk
I have buy a ultrafire 18650 6800mah battery for making DIY power bank, so my question is, is this battery really has 6800 mah? If it is real the I used 4 battery's it means 4X6850=27200mah is that true. Please tell me someone...
No.
On Saturday, December 8, 2018 at 1:27:26 PM UTC-5, snipped-for-privacy@gmail.com wr ote:
o my question is, is this battery really has 6800 mah? If it is real the I used 4 battery's it means 4X6850=27200mah is that true. Please tell me so meone...
Are you connecting the batteries in parallel or in series? If you connect batteries in series the voltages add, but the current rating (mAHr) remains the same. If you connect the batteries in parallel the voltage is the sam e, but the currents are added.
None of this says anything about the accuracy of the claimed 6800 mAHr rati ng of the Ultrafire cells.
Rick C.
Tesla referral code -
My sympathy too. Laser lithotripsy didn't work for me either (as you may recall) but the ultra-sound lithotriptor did.
It did leave me feeling that I'd been punched in the back by something substantial, but that was strictly soft-tissue damage and stopped worrying me after a day lying down and taking as much iboprufen as the label suggests is prudent.
The ultra sound system does seem to break up kidney stones pretty thoroughly.
-- Bill Sloman, Sydney
No. They are junk. My measurements on a single UltraFire 18650 cell shows about 800 ma-hr. Google shows 33 posts by 23 authors all of which indicate that the 6800 ma-hr printed rating is a fabrication and impossible to achieve with even the best consumer grade LiIon 18650 cells available. At best, you might be able to deliver about 2500 ma-hr.
Please read or re-read my original reply to your question, or to someone who may be nym shifting a gmail address:
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
no it's a fake.
-- When I tried casting out nines I made a hash of it.
No 18650 LiIon cell is 6800mAh. Half that would be dreaming.
I can't do ESWL (extracorporeal shock wave lithotripsy). The left rock decided it was time to leave the kidney and ended up stuck in the ureter. The CT scan also showed that it's much too dense at 1500 HU (Hounsfield Units) to fracture with ultrasound. Methinks the limit is
900 HU. I'm scheduled for another CT scan on Monday, and if the stone cooperates, the doctors will be playing laser tag with it on Tuesday. There's a fair chance that I may have already passed the left stone but have no way to tell because I have a stent installed to relieve the back pressure and therefore no pain.Stone Size, Density Matter
I was taking vicodin for the pain. It still hurts, but I didn't care. Imagine a constipated zombie at the keyboard.
Only if the stones are not very dense. My stones don't qualify.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
+1 It is strange that someone without such basic knowledge atempt DIY with Li/ion batteries. I hope you have a good insurance.
Buy some genuine Panasonic NCR cells. They test at their spec, 3400mAh. You'll think you're dreaming, but it's real. :)
The back pressure is from urine backed up behind the stone. The stent is a device to widen the ureter. If the stone is still blocking the ureter the stent can't pass the urine around it... can it?
Yeah, I remember that feeling in the ER a couple of times. When they sent me into the x-ray lab for an IVP the dye backing up behind the stone would both make it start hurting all over again and push the stone out of the kid ney. They've never actually x-rayed one in the kidney until the one I had to have lipsotrypsied. I think it's been nine in total.
ghly.
Mine didn't get broken up so thoroughly, but enough that the pieces eventua lly passed. The doctor was an older guy who didn't give a shit anymore and worked the system to his own advantage. He first tried going in after the stone through the ureter but the stone was too large to take out that way. He claimed he couldn't see that on the x-ray. I'm calling BS on that. H e just wanted to bill for the procedure.
Later he was treating my cousin and I heard the phone call where my cousin needed his weekly prescription of pain killer to be renewed and the doc tol d him he saw where my cousin has scheduled the procedure with someone else who would schedule it sooner. My cousin wasn't going to get his pain meds unless he rescheduled with this doctor! This was on a Saturday when there was zero chance of getting a prescription from any other doctor. What a sh it! The hospital has a new wing named after that doc now.
Rick C.
Tesla referral code -
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