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The only one that makes a greter than 3Ah (3350 mah) 18650 is panasonic Sanyo.
However there are real and good 2200, 2600 and 2800 cells I use the LG2800mah
cells and they are real. However I've seen 2packs of 18650s claiming 4400 mah,
and they were in parallel the cells alone tested at 2200.
With vapers hacking their thing there are a lot of junk cells with outrageous claims.
As to cell size I have tried 18650 at 2800 mah(LG) and it charges properly and
takes about 3 hours. I also tried a Sony 4300mah pouch and it was happy
though it took 5 hours to charge and bulky. Something n the 2100 mah range
with a reasonable form factor is good. However I'm using a set of 1100 mah
cells from a old camera so they can be charged separate if I care to. They
give good run time, charges fast and no noticable battery heating.
It doesn't seem very critical..
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I am using a cell designed for digital cameras ans is 1200mah
and accepts the 1C charge safely. I prefer to keep the charge
rate at .4C, charge time is not an issue as I have three of
them and a holder. Since I'm not doing a race car, fast charge
is not required and tends to beat up the cells.
I use 18650 cells a lot and LD-2800mah would also work well.
I forget where I got it but there is a battery management board
that does over voltage, under voltage and short circuit protection.
Allison
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Interesting...
Over the past week I have casually reviewed various Li-Ion data sources, and I've seen surprising variations.
Up until recently, I had assumed that it was typical to charge a Li-Ion cells at 0.5C.
It appears that depending upon individual manufacturers chemistry variations, that you could expect to be informed
that they will recommend anything from 0.5 to 2.5C !!
But the average is 0.8C.
I'm not convinced that I need to be in a rush to change my own supplied NanoVNA cell.
The specsheet on the VNA indicates anything from a 300-500ma cell, which when supplied may have been sitting
around for a year or two in partly of even fully discharged state before being fitted into a NanoVNA.
Given that expectation, and the current draw of the vna anyway, I'm seeing 2.5 hours of use from a single charge
and no apparent overheating or explosions (!).
Of course, in due course I may see a variation in performance and change my mind ?
Not sure if I'm one of the luck ones, but I've had good fortune with my VNA (Black non Gecko)..
I bought it, it worked, seems as accurate as can be, was dead easy to re-box and just sits there ready for use
when I need it. Perfect !
- Andy -
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I use Ansmann cells in my other projects.
Can sustain 2C charge + has battery management included.
At worst case in a Nanovna, don't charge via USB, but via your own preferred external charger ?
- Andy-
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Hi Andy On Wed, Nov 20, 2019 at 06:37 PM, Andy wrote: OK I started testing the charging current on my NVNA.
Typically 650ma on an empty 400ma supplied cell, oh dear !!! That's 1.625C. Exceeds spec of 1C max. Bad mojo. Please try charging from a USB2 standard port and measure the current. I wasn't expecting that to be honest, I really did assume that there would be
some controller regulating the current. Something is limiting the current given that you were using a 2.1A mains adapter. My guess it is the battery protection module in the battery itself. Search for DW01-P One Cell Lithium-ion/Polymer Battery Protection IC. I consider that the IP5303 datasheet to be a bit misleading in my opinion. It is certainly hard to understand what the charge current will be in practice. Before I did the test, I also measure the current on a supposedly charged
cell, and it wasn't actually any different. My guess is that the battery voltage never reached 4.1V so the IP5303 just kept going.. Guess I'll be modding mine for an 18650 cell shortly. Not convinced this is the best option now. An 18650 would require an external battery protection module. I've been doing some tests using an old cell phone battery. It is a NEC MAS-BD0021-A001 1100mAh Li-Ion. Must be at least 15 years old. From a full charge it will run the nvna for 4 hours before the over discharge protection kicks in. A full charge using a 1A mains adapter takes 3 hours and the charge current never exceeds 400mA i.e. 0.37C. On a USB2 standard port the charge current never exceeds 200mA i.e. 0.18C. Cannot find a spec for this particular battery but that looks good to me. Note that supplied SD 602040 is a Li-Po; the NEC is a Li-Ion battery. The different discharge characteristics may need mods to the discharge table in the firmware. I haven't looked at that yet. 73 Nick
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On Wed, Nov 20, 2019 at 10:11 AM, Larry Rothman wrote: Please DO NOT USE any LiIon battery that is beginning to swell !!!? Recycle it.Once a LiIon battery is starting to swell, its internal chemistry is unstable. Larry, While I appreciate your abundance of caution, I have observed that these flat batteries "just begin" to swell almost immediately (i.e., a fraction of a mm and they will spin on the desk) after only a few cycles, and they continue to slowly expand throughout their useful lives (2-3 years), until they will no longer fit in the phone and the back cover cannot be snapped in place -- and none of them have ever gone exothermic. At that point I discard them in my 55-gallon burn barrel with the trash, and burn them up, without noticeable incident. I think it's likely that the rare ones that do go exothermic have faulty protection circuits, or careless re-purposing; hence my question about the 2 additional terminals. Thanks for the Instructables article; it's good to know the contacts can be soldered without ruining the battery. 73, --kv5r
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On Thu, Nov 21, 2019 at 04:56 AM, Dr. David Kirkby, Kirkby Microwave Ltd wrote: Thnx, dear 9 lined signature sales man.
On Mon, 18 Nov 2019 at 13:58, RFy <gpdxdveil@...> wrote:
450mAh is... Not suitable for NanoVNA
1. Stand-by draw
2. Charge circuit pushes over 1A( over 2C rate )
My battery already swelled( PCB/LCD curved slightly )
There are some high specification batteries for sale on eBay, at quite a
reasonable cost.
Dave.
--
Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...
Telephone 01621-680100./ +44 1621 680100
Registered in England & Wales, company number 08914892.
Registered office:
Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United
Kingdom
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On Thu, Nov 21, 2019 at 01:26 PM, Nick wrote:
Hi Andy
- How did you determine "charged"? LED not flashing?
LED stops flashing and USB current meter shows zero current being drawn (nanovna being switched off). - What did you measure the current with? In line USB tester. Ten for quid from China variety / Ebay ;-) - What was the charge source? USB or something else? Need spec please. 2.1 amp USB cell phone charger, as supplied with my ancient Acer phone. 73 de Andy
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On Wed, Nov 20, 2019 at 06:37 PM, Andy wrote: Typically 650ma on an empty 400ma supplied cell, oh dear !!!
Before I did the test, I also measure the current on a supposedly charged
cell, and it wasn't actually any different. Hi Andy - How did you determine "charged"? LED not flashing? - What did you measure the current with? - What was the charge source? USB or something else? Need spec please.
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Larry, thanks for the translated sheet for the FM9688. This sheet refers to there being 4 programmable charging currents. The two lowest might be appropriate for the NanoVNA with original battery. BUT nowhere does the spec sheet say how it is programmed. The assumption is that one needs to specify this to their factory at the time of purchase. Very little chance of sorting this out when buying one or ten through Ebay!
Brian. 5B4AHW
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On 19 Nov 2019, at 18:57, Larry Rothman <nlroth@...> wrote:
I'm wondering if hugen is able to verify that the replacement battery control chip he is thinking of using will prevent over charging any cells.
I've translated and attached a copy of the FM9688 Mobile Power Management IC spec sheet.
On Tuesday, November 19, 2019, 11:17:19 a.m. GMT-5, Nick <g3vnc@...> wrote:
On Mon, Nov 18, 2019 at 01:58 PM, RFy wrote:
450mAh is... Not suitable for NanoVNA
2. Charge circuit pushes over 1A( over 2C rate )
My battery already swelled( PCB/LCD curved slightly ) Yes. This issue has been reported before (posts #3096, #4533, #6288 etc.)
Supplied nvna battery spec is here...
Maximum Charging Current specified as 450mA.
IP5303 Charging current specified as 1.2A typ and 1.4A max. There does not appear to be any way to reduce this without additional circuitry.
So worst case the 450mAh battery might be charged at 1.4/0.45 = 3.1C !
Qualifies as ultra fast charging...
Charge rate might depend on the source. If the nvna is being charged from a standard downstream USB2 port, such as those fitted to this computer, then the charge current could be limited to 500mA which is ~1.1C.
Might explain why my battery was fine until I subjected it to an iPad charger!
Looking longways on the nvna I can see that the pcb and rear panel are deflected by the battery swelling. Easily verified by removing one screw in the rear panel where a gap opens up between the panel and the brass spacer.
I have now removed the 450mAh battery and temporarily fitted a 1100mAh ex call phone battery stuck on the rear panel.
I will fit a "quality" protected 18650 cell when I assemble the repackaged nvna.
<FM9688 Mobile Power Management IC.pdf>
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WOW!??
Go to your local mobile phone shop/kiosk and just buy a thin/low-profile replacement battery and use that - like I did with my first Gecko Nanovna.
I used a small nut as a spacer under each screw to move the rear panel enough for the 800mAH phone battery to fit.
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On Wednesday, November 20, 2019, 2:47:08 p.m. GMT-5, erik@... <erik@...> wrote: The battery was already swollen when I got the nanoVNA. It is now even more swollen. Only used computer USB2.0 ports to charge, not even USB3.0. Never a separate charger Will contact hugen as I bought from his shop and the battery is glued to the PCB and I do not want to destroy my nanoVNA -- NanoVNA Wiki: /g/nanovna-users/wiki/homeNanoVNA Files: /g/nanovna-users/filesErik, PD0EK
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Only if you fear fire and explosions.
Glenn
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On 11/20/2019 2:14 PM, erik@... wrote: On Wed, Nov 20, 2019 at 08:11 AM, Larry Rothman wrote:
Please DO NOT USE any LiIon battery that is beginning to swell !!!
Should I be worried?
--
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Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178
QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"
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On Mon, 18 Nov 2019 at 13:58, RFy <gpdxdveil@...> wrote: 450mAh is... Not suitable for NanoVNA
1. Stand-by draw
2. Charge circuit pushes over 1A( over 2C rate )
My battery already swelled( PCB/LCD curved slightly ) There are some high specification batteries for sale on eBay, at quite a reasonable cost. Dave. -- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom
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The battery was already swollen when I got the nanoVNA. It is now even more swollen. Only used computer USB2.0 ports to charge, not even USB3.0. Never a separate charger Will contact hugen as I bought from his shop and the battery is glued to the PCB and I do not want to destroy my nanoVNA -- NanoVNA Wiki: /g/nanovna-users/wiki/homeNanoVNA Files: /g/nanovna-users/filesErik, PD0EK
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For the forum members that are unsure of the safety when charging their Nanos, try to obtain a low-current PolyFuse and place it in series with the positive lead on the battery.
You can find info on Polyfuses here:?
I was looking up specs and found this part series that 'should' probably be OK to use as protection.
I attached the datasheet.
NOTE - these devices are used in most modern battery-powered electroinc devices so go through your junk box to see if there might be anything similar you can use.
On the other hand, stick a 22 to 27 ohm resistor in series with the battery to limit the current.
Cheers,??
Larry
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On Wednesday, November 20, 2019, 1:37:42 p.m. GMT-5, Andy via Groups.Io <punkbiscuit@...> wrote:
OK I started testing the charging current on my NVNA.
Typically 650ma on an empty 400ma supplied cell, oh dear !!!
I wasn't expecting that to be honest, I really did assume that there would be some controller regulating the current.
I consider that the IP5303 datasheet to be a bit misleading in my opinion.
Before I did the test, I also measure the current on a supposedly charged cell, and it wasn't actually any different.
Guess I'll be modding mine for an 18650 cell shortly.
Has anyone got a fire extinguisher that they can lend me ;)
73 de Andy
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Erik,
You really do not want to screw around with a swollen LiIon or generally any Lithium type battery that is beginning to swell.
All they are good for is taking them outside in a wide open area, banging a nail through and running up-wind of the smoke and fumes! ;-)
But seriously, working in a two-way radio service shop, I come across all shapes and sizes of batteries and we have to bag each Lithium unit that is recycled in order to prevent shorts to other devices.
Why take a chance on a fire. Lithium reacts to air AND water.
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On Wednesday, November 20, 2019, 2:14:13 p.m. GMT-5, <erik@...> wrote: On Wed, Nov 20, 2019 at 08:11 AM, Larry Rothman wrote:
Please DO NOT USE any LiIon battery that is beginning to swell !!!
Should I be worried? -- NanoVNA Wiki: /g/nanovna-users/wiki/homeNanoVNA Files: /g/nanovna-users/filesErik, PD0EK
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Should I be worried? Not seen a swollen cell catch fie ...yet, but it is rumoured. More likely to cause physical damage to the VNA, or leak nasty stuff that yu might not want to get on your skin or inhale. It should should really be removed asap. 73 de Andy
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OK I started testing the charging current on my NVNA.
Typically 650ma on an empty 400ma supplied cell, oh dear !!!
I wasn't expecting that to be honest, I really did assume that there would be some controller regulating the current.
I consider that the IP5303 datasheet to be a bit misleading in my opinion.
Before I did the test, I also measure the current on a supposedly charged cell, and it wasn't actually any different.
Guess I'll be modding mine for an 18650 cell shortly.
Has anyone got a fire extinguisher that they can lend me ;)
73 de Andy
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Please DO NOT USE any LiIon battery that is beginning to swell !!!? Recycle it.Once a LiIon battery is starting to swell, its internal chemistry is unstable.
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On Wednesday, November 20, 2019, 10:27:54 a.m. GMT-5, KV5R <kv5r@...> wrote:
I figured it out! After earlier posting, I remembered I have a wall charger for those Galaxy S3 batteries; it uses contacts 1 & 3.
And then reading the label on one of them, remembered the NFC antenna. Verified with the bench DMM.
With the battery oriented contacts up and left, and calling leftmost contact #1:
1. DC +
2. NFC loop antenna (2.4k-ohms to #3, either polarity)
3. DC - , and other end of NFC loop antenna
4. n/c (resistance infinite, either polarity)
So I'll take the oldest one (just beginning to swell) and try to solder #30 wires, hopefully without melting the plastic case too much...
Gotta order some 2.5mm standoffs first.
Thanks Guys,
73, --kv5r
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Dr. David Kirkby, Kirkby Microwave Ltd
