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Hack Chat Transcript, Part 2

A event log for Battery Engineering Hack Chat

The power in your pocket

dan-maloneyDan Maloney 12/14/2022 at 21:560 Comments

ILove Scotch12:02 PM
Mods please delete my last link to licap, it's is incorrect and wrong page i linked. these are standard ultracaps.

Dave Sopchak12:02 PM
@ILove Scotch that lithium ion capacitor is not a battery, nor a hybrid. It's a capacitor. Look at that pathetic energy density. You're just shuttling ions, not doing reactions

Dan Maloney12:02 PM
So can you share a little more about how you got mixed up in electrochemistry? Sounds like it might be a cautionary tale...

Dave Sopchak12:03 PM
tbh, my first exposure to it was when I was a little kid and my dad showed me the penny/salt water on a bit of paper towel/nickel battery would make a voltage

Dave Sopchak12:03 PM
within a year I decided, hey how about a sheet of aluminum, a sheet of copper, and bleach? Got enough to run a model motor but fast!

Mark J Hughes12:04 PM
My understanding is that all batteries -- going back 200 years depend on electrochemistry. But if the pundits are to be believed, there's a movement towards quantum (solid-state) batteries that do not make use of ionic movement or chemical reactions. Do you know anything about these next-generation of energy storage devices?

Dave Sopchak12:04 PM
no I don't. You have linky?

Mark J Hughes12:05 PM
Also -- if someone wanted to study battery technology -- what should they start reading to better understand the lingo & problems battery engineers try to address?

Dave Sopchak12:05 PM
so, let's get a few things straight- a solid electrolyte does not a solid state battery make. There are volume changes on *all* battery electrodes depending on the state of charge

anfractuosity12:06 PM
not heard of that before sounds interesting, just looking at - https://physicsworld.com/a/quantum-batteries-harvest-energy-from-light/

Mark J Hughes12:06 PM
Well -- one example: https://patentimages.storage.googleapis.com/22/0c/1d/f485c30d1ed67c/US10395850.pdf

Dave Sopchak12:06 PM
also, the definition of an anode, you know, the one Michael Faraday gave it, is an electrode that does an oxidation. An electrode that does a reduction is a cathode.

Mark J Hughes12:06 PM
(Sorry don't have anything immediately on hand that isn't marketing spiel from some place, so I went to academia)

Peter Smith joined  the room.12:07 PM

Dave Sopchak12:07 PM
it doesn't matter what the voltage of the electrodes are, or if they're charging or discharging, all that matters is what they're doing- oxidation or reduction

richt22 joined  the room.12:07 PM

Dave Sopchak12:07 PM
so despite the fact that the material scientists and others don't know their terminology...

ILove Scotch12:08 PM
Dave I meant this earlier https://en.wikipedia.org/wiki/Lithium-ion_capacitor "The negative electrode or anode of the LIC is the battery type or high energy density electrode. The anode can be charged to contain large amounts of energy by reversible intercalation of lithium ions. This process is an electrochemical reaction."

alex.bailes joined  the room.12:08 PM

Dave Sopchak12:08 PM
this more informal and ever expanding definition of "battery" and other terms kind of muddles the water. I know I can count on you all to fight the good fight!

Dave Sopchak12:10 PM
hey @ILove Scotch OK, but still...they're stretching the definition there. Intercalation takes time. I'd like to see how fast they can charge or discharge it. If it's a battery, it's got a hard upper limit, otherwise you'll plate lithium out and screw up the cell

Dave Sopchak12:10 PM
double layer charging, even in solution, is much faster than a chemical reaction

ILove Scotch12:11 PM
it has properties of both, hence hybrid.

Dave Sopchak12:11 PM
I would hope it cycles faster and longer than a Li battery

ILove Scotch12:11 PM
i.e.

jondaddio12:13 PM
"New High-Performance Solid-State Battery Surprises the Engineers Who Created It" with link at https://scitechdaily.com/new-high-performance-solid-state-battery-surprises-the-engineers-who-created-it/

Dave Sopchak12:13 PM
I mean, at the moment Li ion batteries have Li ions intercalate into graphite on the negative side, and metal oxides of phosphates on the positive side

Dave Sopchak12:13 PM
conversion type electrodes (FeF3), sulfur or Li air? those things give you a different product upon discharge

Dave Sopchak12:14 PM
Fe and LiF, Li2Sx, and Li2O2, respectively

Tom Johnson12:14 PM
What chemistries are realistic to expect in 5-10 years for C&I storage?

Dave Sopchak12:14 PM
what does C&I mean

Tom Johnson12:15 PM
Commercial and Industrial.

Dave Sopchak12:15 PM
ah

Tom Johnson12:16 PM
I assume that batteries will continue to be made of multiple small units, serialized and parallelized into large power/energy blocks.

Dave Sopchak12:16 PM
it's interesting, Li ion has become so damn cheap and long life, it's a tough nut for the other stationary storage types to chase

Thomas Shaddack12:16 PM
what about molten metal batteries? that guy from MIT came up with a simple design with liquid electrodes, density-separated, and liquid molten-salt electrolyte. no membranes, no electrode lattice degradation, no expensive materials, suitable for grid storage.

Dave Sopchak12:16 PM
credit where credit is due- Tesla has done some amazing stuff with 18650s. They still use those in the model S

Dave Sopchak12:17 PM
@Thomas Shaddack are those a flow battery?

Dave Sopchak12:18 PM
folks have always wanted to do sulfur batteries with molten sulfur. Sodium-sulfur with both of them molten

Dave Sopchak12:18 PM
Sodium melts at 97C. Convenient

Thomas Shaddack12:18 PM
@Dave Sopchak Nope. It's the Ambri thing.

Tom Johnson12:19 PM
The ideas of all the connectors on the 18650 blocks give me the heebe-jeebies. I don't have real data for my concerns though.

ILove Scotch12:19 PM
"Undecided with Matt Ferrell" oh god, he gets so many things wrongs at times...

Dave Sopchak12:19 PM
I've heard of Ambri, but don't know specifics

Dave Sopchak12:20 PM
please, @ILove Scotch , all youtube videos are vetted for scientific accuracy!

Thomas Shaddack12:20 PM
undecided is certainly not a gospel but the best i can do as of just now in real time.

Thomas Shaddack12:20 PM
the mit guy has a whole lecture but that one is LONG.

Dave Sopchak12:20 PM
I can look at it and get back to you

ILove Scotch12:20 PM
@tom should ask me, I got tons of tesla battery info lol.. sitting at my desk is Model s module, tesla Roadster module, and i'm building my own 18650/27.... lego module for future designs.

Dave Sopchak12:20 PM
Professors, man, they just go on and on. I should know, that's what I used to do

Dave Sopchak12:21 PM
very cool!

Dave Sopchak12:21 PM
those 18650s are still the highest energy density cells Tesla has, iirc. The bigger ones can deliver and take more current, but at a bit of a cost in energy density

Dave Sopchak12:22 PM
also the 18650s can be cooled better than the bigger cells

Thomas Shaddack12:22 PM
Flow batteries have that annoying membrane thingy. Though I saw a design of a chlorine flow battery, with water-tetrachlormethane (or water-hydrocarbon) systems, where there is no membrane, and the catholyte-anolyte junction is between immiscible liquids. The water phase is chloride-rich, the organic phase is solvent for chlorine. The junction happens on a layer of activated carbon with titanium-ruthenium oxide catalyst.

Tom Johnson12:22 PM
Is it clear that LFP (Lithium Iron Phosphate) is the safest battery for inside-the-building applications?

Dave Sopchak12:22 PM
what's so annoying about a membrane (or a porous separator)

ILove Scotch12:22 PM
Agreed on FLow, PEM are expensive (to me anyways)

Dave Sopchak12:23 PM
when I did flow batteries, we used a porous separator

Dave Sopchak12:23 PM
Don't get me started on Nafion. I spent my whole fuel cell career showing them up ;)

Dave Sopchak12:24 PM
@Tom Johnson yeah for existing Li ion types LiFePO4 is pretty safe, can handle higher temps...

Thomas Shaddack12:24 PM
Dead Li-ion cells, especially the pouch ones that are easy to disassemble, are a pretty good source of microporous polyolefin membranes. Pretty handy for electrochemistry.

Thomas Shaddack12:24 PM
Is there an alternative to Nafion?

Dave Sopchak12:24 PM
sure. Sulfonated styrene-ethylene

Drix12:24 PM
@Dave Sopchak: you mentioned earlier that there's no solid state battery*.

=>But do you know of a technology that allows a higher density / compactness, for (extreme) miniaturization?

*refering to this:

https://www.electronics-lab.com/meet-the-tiny-100mah-rechargeable-3d-solid-state-batteries-from-iten/

Dave Sopchak12:24 PM
Thomas- yes. Celgard separators

Dave Sopchak12:26 PM
hi @Drix the reason solid electrolytes do well in teeny batteries is because the teenier the battery, the less likely the thin solid electrolyte will fail due to volume changes on change in state of charge

kjansky112:27 PM
Any developments on radioisotope batteries?

Dave Sopchak12:27 PM
that's one of the things that's hiding behind the misnomer "solid state". If they are truly solid state, why do things crack and fail, or why do dendrites get through? Solid state devices don't fail that way in normal operation

Thomas Shaddack12:27 PM
We did some experiments with laser-induced pyrolysis of kapton for graphene supercaps. With ionic liquid as electrolyte. It worked pretty well, we used the dead-battery separators with success. Also tested briefly for testtube-scale hydrogen production, also works.

Dan Maloney12:28 PM
@kjansky1 What, like the RTGs on the Mars rovers?

Tom Johnson12:28 PM
Speaking of dendrites...any way of breaking them up by vibration?

Dave Sopchak12:28 PM
a radioisotope battery is a betavoltaic, is that what you mean?

Dave Sopchak12:28 PM
or the RTGs?

kjansky112:28 PM
Yes.

Thomas Shaddack12:29 PM
Solid state devices love to fail. Electromigration, in chips. Growth of intermetallic phases on bonding. Cracks and delamination on thermal cycling. And on and on and on...

Dave Sopchak12:29 PM
yeah Tom also breaking up the solid electrolyte with vibration

Dave Sopchak12:29 PM
yes and flash memory with ungodly high potential gradients in the gate

kjansky112:29 PM
RTGs are just fancy thermocouple generators.

Tom Johnson12:29 PM
@Dave Sopchak You confused my sarcasm detector.

Dave Sopchak12:29 PM
@kjansky1 so you mean betavoltaics

Dan Maloney12:29 PM

https://hackaday.com/2019/02/08/the-deep-space-energy-crisis-could-soon-be-over/

HACKADAY DAN MALONEY

The Deep Space Energy Crisis Could Soon Be Over

On the face of it, powering most spacecraft would appear to be a straightforward engineering problem. After all, with no clouds to obscure the sun, adorning a satellite with enough solar panels to supply its electrical needs seems like a no-brainer.

Read this on Hackaday

Tom Johnson12:30 PM
@Dan Maloney Definitely not a battery. ;)

Thomas Shaddack12:30 PM
...and trapping the charge carriers in the oxide and resulting in wear in a similar mechanism as a radiation damage. (random thought, could that damage be annealed by heating the worn flash chips for prolonged period?)

Dave Sopchak12:30 PM
I did a little work with betavoltaics when I was at LLNL

Dave Sopchak12:30 PM
@Tom Johnson gets it ;)

Tom Johnson12:31 PM
Its now one of the 7 things in my head.

Dave Sopchak12:31 PM
so @kjansky1 betavoltaics (let's say one using tritium)- these things have ungodly high energy densities, but, you can only pull as much current as the betavoltaic is spitting out electrons

Dave Sopchak12:32 PM
so, long use, low current. You could combine one with a battery or a cap to trickle charge it for higher current demands

Thomas Shaddack12:32 PM
low current does not matter when paired with a supercap for pulsed loads, and used for a sensor that squirts data once per time.

Dave Sopchak12:32 PM
@Thomas Shaddack great minds....

anfractuosity12:32 PM
Do you have an idea how much power a plutonium RTG that used to be used in a pacemaker, might be able to produce at it's peak

Dave Sopchak12:32 PM
wat

kjansky112:33 PM
Problem with H3 is its relatively short half life.

Dave Sopchak12:33 PM
they put a plutonium RTG in a pacemaker?!?!?!

anfractuosity12:33 PM
yup

Dave Sopchak12:33 PM
oy

Dan Maloney12:33 PM

https://www.medicaldesignandoutsourcing.com/looking-back-the-plutonium-powered-pacemaker/

MEDICAL DESIGN AND OUTSOURCING SAM BRUSCO

Looking Back: The Plutonium-Powered Pacemaker

The pacemaker has certainly had an interesting journey from its inception-it started as a hand-cranked box that, ironically, scared the life out of people because it leaned a little too close to Frankenstein-esque reanimation. Since then, the smallest model (Medtronic's Micra TPS) is about the size of a large vitamin, with a battery life of up to ten years.

Read this on Medical Design and Outsourcing

Dave Sopchak12:33 PM
@kjansky1 what kind of time frame were you looking for? 12 year half life not good enough for you I guess

Thomas Shaddack12:34 PM
Carbon-14 could be used instead of tritium.

Dave Sopchak12:34 PM
well Pu is a alpha emitter

Dave Sopchak12:34 PM
oh yes we did that at LLNL too

kjansky112:35 PM
You can use both alpha and gamma emitters with charge induction in a semiconductor junction.

Dave Sopchak12:35 PM
and when C14 decays, you get nice N14.

Thomas Shaddack12:35 PM
H3 gets even nicer He3. N14 is rather annoyingly common.

Dave Sopchak12:36 PM
I'm not an expert on the alpha/beta/gamma voltaics, but I'm not clueless

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