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Why Donut labs solid state battery could be real

tmichael said:
I still have 160K floppies and started playing on a Sinclair in England, running basic.

Of course, that was before software bloat....

Did I mention that I had to walk to school, uphill both ways, with only newspapers for shoes? 😅
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Floppies???? Sounds like a step up from punched paper tape which was my first programming experience with basic.

Honestly, the most fun probably was learning to program an analog computer. Envision switchboard like panels of patch wires, pots, etc., to create systems of differential equations. Output was via ink pen strip chart plotters. Most frustrating part was invariable one of the pens would clog/dry up right in the middle of running the simulation.

Oh the olden days!!!
 
PCMc said:
Floppies???? Sounds like a step up from punched paper tape which was my first programming experience with basic.

Honestly, the most fun probably was learning to program an analog computer. Envision switchboard like panels of patch wires, pots, etc., to create systems of differential equations. Output was via ink pen strip chart plotters. Most frustrating part was invariable one of the pens would clog/dry up right in the middle of running the simulation.

Oh the olden days!!!
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Ah the good old days... when the longest part of programming was filling out the punch cards.😅 I think there's an old Kaypro in the garage somewhere...
 
scal_air said:
Ah the good old days... when the longest part of programming was filling out the punch cards.😅 I think there's an old Kaypro in the garage somewhere...
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And the most indispensable and valuable piece of technology one had was a magic marker… to draw diagonal lines along the edge of your punch card stack in the event you dropped it. 🙄
 
TomUH said:
And the most indispensable and valuable piece of technology one had was a magic marker… to draw diagonal lines along the edge of your punch card stack in the event you dropped it. 🙄
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Damn! Never did that - that would have helped alot!
 
There is one unanswered question for me: how long does the cell hold a charge? What is the parasitic discharge rate?

All the test results match a high capacity capacitor. Is it really a battery that can hold a charge for a very long period of time?
 
Saksak said:
There is one unanswered question for me: how long does the cell hold a charge? What is the parasitic discharge rate?

All the test results match a high capacity capacitor. Is it really a battery that can hold a charge for a very long period of time?
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I agree this is an important test to see data and this release was largely…meh. Yes it does better at high temp and I could see this increasing efficiency by simply having far less bms cooling.

I also want to see data verifying energy/weight and cycles, especially since v2h and potential to have your “old car” work with solar/wind inputs to enable taking your house off grid and off grid building for long term. The cold energy profile would be interesting for its use in cold climates in evs, but also for higher speed/elevation planes and drones. I would like to know their manufacturing process, but I don’t think we are going to get that.
 
Saksak said:
There is one unanswered question for me: how long does the cell hold a charge? What is the parasitic discharge rate?

All the test results match a high capacity capacitor. Is it really a battery that can hold a charge for a very long period of time?
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The voltage versus SOC curve looks more like a regular Lithium NMC battery than a capacitor. I agree that there are still a lot of unanswered questions including the ones you are asking.
 
Interestingly, after the last test,
"The cell was also discharged at +100 °C using a current of 12 A, achieving 107.1 % of the reference discharge capacity measured at +20 °C using the same current. After the discharge, the cell was able to be charged normally; however, the cell pouch was observed to have lost its vacuum."

But no mention of a fire. If I'm not mistaken, a conventional lithium NMC cell may spontaneously ignite some time after it loses hermeticity.
 
this is an interesting/infomative video that answers some of the above questions:
 
the latest from Donut Labs in their weekly installment of tests of their supposed solid state battery. This is an attempt to show that the battery isnt, as some have alleged, a supercapacitor.
 
LuHart said:
the latest from Donut Labs in their weekly installment of tests of their supposed solid state battery. This is an attempt to show that the battery isnt, as some have alleged, a supercapacitor.
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Cliff notes, yes I remember these:
1. Energy storage is stable over the 10 day period without use.
2. Equivalent energy storage stability with current lithium battery tech.
It is only one cell, at one temp, and at one soc, which isn’t ideal, but this is huge that it outright shows it holds charge like a battery is expected to when not used for up to 10 days. I hope lucid has seen other data before revealing they reveal it in their 2027 lineup in a few days!! Unfortunately, not holding my breath.
 
So I think I'm correct here but if one has a 200KWH battery and a 250KW charging station then charging from 0% to 100% would take 48 minutes wouldn't it? So while it might be possible to charge the battery quicker the charging infrastructure doesn't support these "full charge in 5 minutes" claims (or the SSB size is so small as to be useless in and automobile?).

Are the charging curve's linear or does the take up rate slow as the SSB approaches 100% SoC?

Am I missing something in the time to charge calculation?
 
ke2 said:
So I think I'm correct here but if one has a 200KWH battery and a 250KW charging station then charging from 0% to 100% would take 48 minutes wouldn't it? So while it might be possible to charge the battery quicker the charging infrastructure doesn't support these "full charge in 5 minutes" claims (or the SSB size is so small as to be useless in and automobile?).

Are the charging curve's linear or does the take up rate slow as the SSB approaches 100% SoC?

Am I missing something in the time to charge calculation?
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Your logic sounds logical except for a couple of small points, usually in very tiny print. At the EA stations where I charge, the 350kW is never reached because there are other vehicles hooked up to multiple chargers. The capacity of the substation is usually the limiter. Also, if it's really hot, the charger will usually throttle down to protect itself. I have never gotten over 210 kW, and usually for less than 10 minutes before the charger throttles down. YMMV.
 
ke2 said:
So I think I'm correct here but if one has a 200KWH battery and a 250KW charging station then charging from 0% to 100% would take 48 minutes wouldn't it? So while it might be possible to charge the battery quicker the charging infrastructure doesn't support these "full charge in 5 minutes" claims (or the SSB size is so small as to be useless in and automobile?).

Are the charging curve's linear or does the take up rate slow as the SSB approaches 100% SoC?

Am I missing something in the time to charge calculation?
Click to expand...
You are right that for this setup you would need megawatt charging infrastructure for it to max out. However, the battery management system in the car will also restrict charge speed so the charging curve you get is not linear. This is why most car companies advertise their 0-80% charge time because this portion of charging is usually as good as it gets. The final 20% takes a long time. If you need an adapter for the DC charger, that is usually a bottleneck too as it will constrict charge speed so it’s current level isn’t exceeded.
 
Dolphins4ever said:
You are right that for this setup you would need megawatt charging infrastructure for it to max out. However, the battery management system in the car will also restrict charge speed so the charging curve you get is not linear. This is why most car companies advertise their 0-80% charge time because this portion of charging is usually as good as it gets. The final 20% takes a long time. If you need an adapter for the DC charger, that is usually a bottleneck too as it will constrict charge speed so it’s current level isn’t exceeded.
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But isn't the final 20% charge time a function of the battery chemistry? Would a SSB allow a consistent charge percentage from 0% to 100%?
 
Dolphins4ever said:
You are right that for this setup you would need megawatt charging infrastructure for it to max out. However, the battery management system in the car will also restrict charge speed so the charging curve you get is not linear. This is why most car companies advertise their 0-80% charge time because this portion of charging is usually as good as it gets. The final 20% takes a long time. If you need an adapter for the DC charger, that is usually a bottleneck too as it will constrict charge speed so it’s current level isn’t exceeded.
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My understanding is that one of the big benefits of solid state batteries is that the charging is linear; that is, the charging rate doesn't taper off as you approach 100% SOC. OTOH, the charger itself would probably throttle down due to heat buildup. So the weak link would be the charger and not the SS battery.
 
Self discharge rate of the Donut lab battery - screenshot from YouTube:
IMG_0047.webp


It’s much higher than current batteries, but I’d be willing to live with the trade-off.

The testing lab was independent, but the exact test procedure was dictated (and paid for) by Donut labs with specific batteries provided for each test. All this means is that the numbers were not fabricated. It’s far the battery being validated by an independent third-party.

I’m not saying the claims aren’t true. I’m saying we don’t know, and won’t until the battery is tested by a truly independent third-party.
 
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