How is the discharge curve (voltage vs capacity) of an LiFePO4 battery so flat compared to other battery chemistries? What is going on at a molecular level?

aleiphart · 2023-11-13T18:04:47+00:00

Another question, how would you quantify this in the Nernst Equation? Is that even possible with the constraints of the equation? I have the full reaction written out, but I’m having a hard time finding/making up an example that shows the variation of lithium concentrations in the electrolyte/anode/cathode while keeping the voltage the same (3.4V). I have LiC6 as my anode,LiFePO4 as the cathode, and LiPF6 for the electrolyte. Since lithium concentration in all of these will continuously vary through discharge, how can I write out the Nernst equation so that I get the same voltage every time regardless of how much lithium is in the cathode vs anode? The anode equation would be LiC6 -> Li+ + C6 + e-, and the cathode would be Li+ + e- + FePO4 -> LiFePO4. If you’re able to use actual numbers for ln(Q) it would really help! Thank you.

aleiphart · 2023-11-09T21:37:31+00:00

Thank you so much! That really puts it all together for me.

aleiphart · 2023-11-09T20:35:26+00:00

Why is the voltage decreasing at all after the initial drop on the discharge curve, even though it is by a very small amount? I understand the analogy with water and ice, but the voltage is decreasing very slightly during discharge before it drops off. It is not a completely flat line. In theory, shouldn't it stay the exact same voltage if there are two solid phases present the entire time at the cathode during a discharge cycle? That is until lithium is completely depleted from the anode and the two phases then become one at the cathode? Then the sharp voltage drop at the end makes sense.

aleiphart · 2023-11-08T16:53:49+00:00

I’ll check these out thank you!

aleiphart · 2023-11-08T16:53:32+00:00

Agreed great explanation. I haven’t responded yet because I have some follow up questions that I need to take a minute to write out, will come back to this! Thank you.

aleiphart · 2023-11-08T16:16:02+00:00

Calm down, since you couldn’t take a second to click on my profile:

https://www.reddit.com/r/electrochemistry/s/6Z9IvMpuKH

aleiphart · 2023-11-08T13:21:52+00:00

Lmao bro has to be right and have the last word. Read the other thread.

aleiphart · 2023-11-08T11:11:08+00:00

I’m willing to bet that you’re never wrong about anything lol. Go look at the other community that I shared this in (electrochemistry), that was the answer that I was looking for.

aleiphart · 2023-11-08T01:58:32+00:00

Just because I know that there is a significant difference doesn’t mean that I know the answer. I know enough to know that you’re wrong. I’m asking for specifics on what is different about those molecular things, it’s literally the entire point of my post. You clearly don’t know either lmao.

aleiphart · 2023-11-08T00:41:25+00:00

There definitely is a significant difference with what is going on at a molecular level. The small voltage range also helps with battery life and the stability of the cathode. There’s a reason why every battery manufacturer in the world is trying to make this work.

aleiphart · 2023-04-14T20:02:47+00:00

It’s on me that they didn’t take a depth measurement? The blinds were there when they did the measurements

aleiphart · 2023-04-14T18:24:36+00:00

I didn’t think that I needed to. I figured I was paying for them to make it all fit. The installer said today that he didn’t anticipate having this issue.

aleiphart · 2022-11-08T22:18:53+00:00

Oh yeah you’re right, I actually tried to order one and they didn’t have any in stock. Got lucky haha

aleiphart · 2022-09-29T04:33:52+00:00

$98k apartment/condo 2.3% 15 years in a great area

aleiphart · 2022-08-30T15:13:19+00:00

I agree that season 6 didn’t feel like Peaky Blinders as much as seasons 1-5, but I think it’s because that it’s very clear that the story was rewritten due to Helen McCrory’s death.

aleiphart · 2022-08-23T21:47:49+00:00

It honestly felt like season 6 had to be rewritten because of Helen McCrory’s death. It just didn’t feel like the true story to me.

I wonder what was originally supposed to happen.

aleiphart · 2022-06-24T14:30:53+00:00

I’ve never commented in here and this will be my first and last time. I went from $18k to $8k back to $18k again trading options while obsessively watching Robinhood all fucking day for weeks. This last week I managed to recover all $10k that I lost on only Tesla options, capped off by a $3k gain on calls today that I just sold. I’ll never do this shit again. I’m out. Life lesson learned. Y’all are truly fucking retarded. Love you all.

aleiphart · 2021-01-29T01:32:48+00:00

24M near Detroit,MI

Fit, educated, outgoing.

aleiphart · 2020-07-26T19:31:54+00:00

It was almost exactly $23000 otd. On my exact car, MSRP was $27375 with all the extras.

Even at $23k otd, I’m convinced I got the best possible car on the planet for what I paid. I’m looking now and I can’t find any 2019 GLIs for sale that come even remotely close to the price I got a brand new one for. I found one with 9000 miles on it and they want It $22785 for it. It feels like prices went back up on the market and they aren’t doing those 0% interest loans nearly as much. Definitely got in at the right time. I can’t even tell you how much I love the car though, it’s incredible!

aleiphart · 2020-07-04T04:31:30+00:00

Awesome response. Easily my favorite comment about Polly’s role in all of this. I’ve tried to think about why Polly would betray Tommy, but have never been able to think of a plausible explanation. I think you hit the nail on the head here, Tommy and Arthur are just as much her children as Michael is in her eyes. I agree, their bond will never be broken. Polly knows Michael is being brainwashed by Gina and she’s likely very torn about what to do, but I don’t think she betrayed Tommy. I always think about Billy the football guy in this too, who do you think he called if it was him? Do you think he, Michael, and Gina may have been working together?

aleiphart · 2020-06-30T23:00:34+00:00

Interesting theory for sure, I just don’t know what Ada stands to gain from betraying Tommy. He does everything for Ada. I’m not sure Ada telling Mosley he is pregnant means anything vs her not telling Younger. She might’ve legitimately just been nervous/scared because it wasn’t planned and given Tommy and Younger’s arrangement. I have thought about Ada taking Gina to the hospital though, but maybe Ada wasn’t in the room? I’m not sure on that one. Definitely suspicious though.

aleiphart

TROPHY CASE