Are you done stocking up?

[Rossum]

Or maybe it is 7.2v's in Parallel? Or maybe it is just a single 11.1V 8000mAh Li-Po. I Dunno?

There's no such thing as 7.2V or 11.1V Li-ion cells. 7.2V would be two 3.6V cells in series and 11.1V would be three in series.

The problem with putting cells in series, especially in a fixed enclosure, is that you then really oughta balance-charge them. Circuitry to do that exists of course, but it adds cost. Is that less or more the difference between buck-only and boost-buck? I dunno.

FWIW, a common arrangement in BEV and PHEV cars is a "400V" battery which consist of 96 cells in series (and depending on the size of the battery, there may be some paralleling as well). Yes, cars balance-charge. batteries in 'em generally come with 8 year warranties.

 

[zoiDman]

Didn't say they were 7.2v or 11.1 Cells.

The Long and the Short of it is there is a Couple of ways to a Given Multiple of 3.6 or 3.7 and a given mAh. And for all I know there is something like this 2S Smushed into that Enclosure.

https://www.amazon.com/ROARINGTOP-Battery-8000mAh-Batteries-Associated/dp/B08XB1JP3R

Heck, maybe it has Repurposed Cellphone batteries in Parallel with a Buck Circuit? Hopefully Ed will enlighten us with some Inner Pics when his units arrives.

 

[BillW50]

FWIW, a common arrangement in BEV and PHEV cars is a "400V" battery which consist of 96 cells in series (and depending on the size of the battery, there may be some paralleling as well). Yes, cars balance-charge. Batteries in 'em generally come with 8 year warranties.

And sitting on that many lithiums, bad things can happen.

 

[Rat2chat2]

And sitting on that many lithiums, bad things can happen.

Well, let's just add buses to my list of things that scare the bejesus out of me.

 

[Rossum]

And sitting on that many lithiums, bad things can happen.

What's most interesting about that incident is that those buses were using ostensibly "safer" "solid state" LMP batteries. What does "LMP" stand for? Lithium METAL Polymer. Conventional Li-ion batteries contain no metallic lithium, only lithium salts in their electrolyte, but these do!

Why would anyone think that a battery containing substantial amounts of metallic lithium is safer than a conventional Li-ion battery?

lithium is highly reactive and flammable, and must be stored in vacuum, inert atmosphere or inert liquid such as purified kerosene or mineral oil.

 

[Ed Brown]

Hopefully Ed will enlighten us with some Inner Pics when his units arrives.

Yeah, that's why I bought two - one to use and one to take apart and break. However after they arrive and I have a chance to try them out, I'll provide a full report.

One point I made is that if the 8000 or whatever mAH power bank charges two 3000 mHA batteries, the power bank has only 2000 mAH left. I know from battery curves, and we all know this, that as a battery discharges the voltage declines slowly. Thus the 3.7 to 4.2 V operating range of the batteries. So as the power bank is discharging to charge the battery, it's voltage is following a slowly declining curve plotted against time. At the same time, as the battery is being charged, the battery's voltage is following a slowly rising curve, also plotted against time. When those curves cross each other charging stops. That's my hypothesis, and it's supported by the story I told about charging my cell phone.

 

[Ed Brown]

So maybe that's why the power bank is rated at 5V. As it discharges the voltage declines and hopefully ends up around 4V when it's discharged. That would enable it to fully charge the 18650's.

 

[zoiDman]

So maybe that's why the power bank is rated at 5V. As it discharges the voltage declines and hopefully ends up around 4V when it's discharged. That would enable it to fully charge the 18650's.

That's Not how a 5V USB Supply is supposed to work. Or what the USB Standard allows.

So I predict that it will work just like a VV Mod where the Output Voltage is set at 5V. The Output Voltage at the USB Port will be CONSTANT until the Power Bank can't make 5 Continuous Volts, then it will shut off. And the Power Ban will need to be Recharged.

 

[zoiDman]

And sitting on that many lithiums, bad things can happen.

Wow... Talk about a Bad Day at the Bus Stop.

 

[Ed Brown]

That's Not how a 5V USB Supply is supposed to work. Or what the USB Standard allows.

So I predict that it will work just like a VV Mod where the Output Voltage is set at 5V. The Output Voltage at the USB Port will be CONSTANT until the Power Bank can't make 5 Continuous Volts, then it will shut off. And the Power Ban will need to be Recharged.

Interesting. That thing is smarter than me. Maybe I should get a a DNA chip.

 

[zoiDman]

Interesting. That thing is smarter than me. Maybe I should get a a DNA chip.

Just keep in mind that those USB Output Ports on your Solar Battery Bank aren't doing any charging. All they do is supply 5V Constant Output.

For say an LED Light, or maybe an MP3 Player, or some type of USB Powered Charger (that does the Actual Charging).

 

[UncLeJunkLe]

Why would anyone think that a battery containing substantial amounts of metallic lithium is safer than a conventional Li-ion battery?

You know the answer to that. I do too but it's illegal in at least 5 countries to say it in 2022, UK being one of those countries.

 

[UncLeJunkLe]

18650BS has some popular OEM batts on sale

Deal of the Day - Coupons and Specials - 18650 Battery Store

Molicel P42a 21700 - 6.99 4.50
Molicel P28a 18650 - 5.99 4.99
Samsung 40T(3) 21700 - 5.99 4.99

 

[AvaOrchid]

18650BS has some popular OEM batts on sale

Deal of the Day - Coupons and Specials - 18650 Battery Store

Molicel P42a 21700 - 6.99 4.50
Molicel P28a 18650 - 5.99 4.99
Samsung 40T(3) 21700 - 5.99 4.99

Thank you I needed to take advantage of that lol I've got all these 21,700 mods now and I'm using 20700 batteries

 

[Ed Brown]

Yes AvaOrchid, get thee some 21700's. The P42a is a real workhorse.

I still have batteries that I bought in January of 2021 that I haven't used yet. In my vaping career, I've disposed of only two 18650 batteries that were overdischarged. I have some 18650's that have to be 6 years old and are working fine. Who cares if they don't last as long. Always carry plenty of spares and have a good number of batteries in rotation.

 

[Ed Brown]

Well I got the solar charger. It seems well made. The solar cells are rated for 1.2 Watts, at 5volts I presume.
So the solar panels are delivering 0.24 Amps.

After about a week the solar charger is keeping my cell phone going with no additional input. Next maybe a regulated mod....

If I charge it in the sun for 1 hour, that would collect enough energy to vape at 100 watts for 43 seconds.

 

[Ed Brown]

Well I got the solar charger. It seems well made. The solar cells are rated for 1.2 Watts, at 5volts I presume.
So the solar panels are delivering 0.24 Amps.

After about a week the solar charger is keeping my cell phone going with no additional input. Next maybe a regulated mod....

If I charge it in the sun for 1 hour, that would collect enough energy to vape at 100 watts for 43 seconds.

Did anyone check my math above?

 

[BillW50]

Did anyone check my math above?

No, we had taken your word on it.

 

[gloopdegurp]

My brain started bothering me with some "what if...?" scenarios, so I picked up another bottle of base from a different vendor so as to diversify my stash a bit. (and make brain relax a little)

I did another bargain bin binge run and grabbed some more RDAs and one of the two Serpents that I had left behind last visit.
I really am trying to not be greedy and hoard them all, but I did give other folks two weeks to snag them.
And now I have a perfectly rational excuse to go back in another two weeks - to rescue that last Serpent if it continues to be neglected.

Getting ever closer now, maybe just one or two more things...

 

[hittman]

My brain started bothering me with some "what if...?" scenarios, so I picked up another bottle of base from a different vendor so as to diversify my stash a bit. (and make brain relax a little)

I did another bargain bin binge run and grabbed some more RDAs and one of the two Serpents that I had left behind last visit.
I really am trying to not be greedy and hoard them all, but I did give other folks two weeks to snag them.
And now I have a perfectly rational excuse to go back in another two weeks - to rescue that last Serpent if it continues to be neglected.

Getting ever closer now, maybe just one or two more things...

That serpent must be sad sitting there all alone.