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Tesla 4680 Asymmetric Lamination Rumors // Two Cells in One?

发布时间 2024-02-14 17:56:03    来源
Welcome back everyone, I'm Jordan Geisigee, and this is The Limiting Factor. Joe Tegbier recently posted on X that Tesla is trialing asymmetric lamination of their electrodes for their 4680 battery cells, which is expected to contribute to a 10-20% increase in energy density. Normally, I don't cover rumors, but asymmetric lamination appears to be a technology with a lot of potential that, strangely, there's almost no research on. By doing a video on the topic, I'm hoping to draw some experts out of the woodwork for feedback because it almost looks too good to be true.
大家好,欢迎回来。我是乔丹·盖西吉,这里是《极限因素》节目。乔·泰格比尔最近在X上发表了一篇帖子,称特斯拉正在对他们的4680电池进行非对称层压试验,预计能够使能量密度提高10-20%。通常我不涉及谣言,但非对称层压似乎是一种具有很大潜力的技术,然而奇怪的是,几乎没有相关研究。通过制作这个视频,我希望能够吸引一些专家提供反馈,因为这几乎看起来太好以至于让人难以置信。

So today, I'm going to walk you through what I think asymmetric lamination is, how it might improve the energy density of the 4680, and the challenges it faces, like cycle life and manufacturing issues. Before we begin, a special thanks to my Patreon supporters, YouTube members and Twitter subscribers, as well as Rebellionair.com. They specialize in helping investors manage concentrated positions. Rebellionair can help with covered calls, risk management, and creating a money master plan from your financial first principles.
今天,我打算为大家介绍一下我对非对称层叠技术的看法,这种技术如何可能改善4680电池的能量密度,并且面临的挑战,比如循环寿命和制造问题。在我们开始之前,特别感谢我的Patreon支持者、YouTube会员和Twitter订阅者,还有Rebellionair.com。他们专门帮助投资者管理集中头寸。Rebellionair可以帮助您进行看涨期权、风险管理,并从您的财务基本原则中制定一项理财总体规划。

Additionally, for this video, thanks to Billy Wu, Yuka Joravanen, Tom Vaid, and Dr. Yuho Heiska on X, who helped me piece together an understanding of how the electrochemistry of an asymmetric electrode might work. If you're on X, give them a follow.
此外,对于这个视频,我要特别感谢 Billy Wu、Yuka Joravanen、Tom Vaid 和 Dr. Yuho Heiska 在 X 上对我阐释不对称电极的电化学原理方面所给予的帮助。如果你也在X上的话,可以关注一下他们。

Let's start with the source of the asymmetric lamination rumor. Joe Techbier does regular drone flyovers of Giga Austin, where Tesla's 4680 production is located. But more than that, has become a valuable source of intel and analysis on Giga Austin. I highly recommend following Joe on YouTube and X if you're interested in the developments there. But as always, even with trusted sources, information can often get garbled as it passes between people. With that in mind, let's evaluate the rumor.
让我们从关于不对称层压铺陈(asymmetric lamination)谣言的来源开始。Joe Techbier定期使用无人机对特斯拉的4680电池生产基地——Giga Austin进行飞行监测。除此之外,他还成为了Giga Austin的情报和分析宝贵来源。如果你对该地区的发展感兴趣,我强烈推荐关注Joe在YouTube和X上的内容。但正如常情,即使是信任的消息源,信息在传递中往往容易变得混乱。在这种情况下,让我们评估一下这个谣言。

Joe's post states that Tesla is, quote, trialing asymmetric lamination, with one side of the laminated material thicker than the other. The expectation is this will increase the amount of jelly roll that can fit into the 4680 can. End quote. For those who aren't familiar with the construction of a battery cell, the jelly roll is a roll of several layers of plastic, metal, and active material that's inserted into the cell can, soaked in electrolyte liquid, and then sealed during the manufacturing process. On screen is how one set of layers in the jelly roll look in a cross-sectional microscopic view.
乔的帖子表明,特斯拉正在试验非对称层压,其中层压材料的一侧比另一侧厚。预期这将增加4680型电池罐中可容纳的果冻卷数量。对于不熟悉电池单元构造的人来说,果冻卷是由几层塑料、金属和活性材料卷成一卷,插入电池罐中,浸泡在电解液中,然后在制造过程中密封。屏幕上显示了果冻卷中一组层的横截面显微视图。

The negative electrode or anode, there's a copper foil that's coated with graphite. There's an inner and outer separator to electrically isolate each set of layers, and for the positive electrode or cathode, there's an aluminum electrode foil that's coated with particles that contain lithium metal oxide. The graphite anode and the lithium metal oxide cathode are the parts of the battery cell that participate in the chemical reactions that store and release energy. That is, they're active materials. And although the rest of the materials like the current collectors do serve a function, they're considered inactive because they don't store or release energy.
负极或阳极上有一层涂有石墨的铜箔。内外部有隔离层以电气隔离每一组层面。正极或阴极上有一层涂有含有锂金属氧化物颗粒的铝电极箔。石墨阳极和锂金属氧化物阴极是电池电芯中参与储存和释放能量的化学反应的部分,也就是我们所说的活性材料。虽然其他材料(如电流收集器)也有一定的功能,但它们被认为是非活性材料,因为它们不储存或释放能量。

So when Joe says that asymmetric lamination will increase the amount of jelly roll that can fit in the 4680 can, what he likely means is increasing the ratio of active to inactive material. An obvious way to do that would be to laminate a thicker coating of cathode and anode material onto the electrode foils. That in turn would increase the energy density of the 4680 by increasing the proportion of energy storing material in the cell can. So why don't battery cell manufacturers, Tesla included, just laminate the active material as thick as possible on both sides of the electrode foil to increase energy density.
所以当乔(Joe)说不对称层压将增加可容纳在4680电芯中的卷曲胶状物的数量时,他可能指的是增加活性与非活性材料的比例。一种明显的方法是将更厚的正极和负极材料层压到电极箔上。这反过来将通过增加电池中储能材料的比例,提高4680的能量密度。那么为什么电池制造商(包括特斯拉)不只是尽可能地在电极箔的两侧层压活性材料来增加能量密度呢?

Two reasons. First, because with a typical wet coating technique, when the electrode is coated too thick it can cause defects in the electrode. For example, as one viewer, LifeWalk pointed out, the anode can stratify into its component materials during the drying process. As a result, for a single layer lamination, cell manufacturers usually coat the electrode with 50 to 80 microns of active material. However, Tesla doesn't use a wet coating technique. Instead, they use a dry coating process where the active material, polymer binder, and conductive carbon powder are mixed into a kind of dough. And then laminated onto the current collector using heat and pressure.
原因有两个。首先,使用典型的湿涂层技术,当电极被涂层得太厚时,会导致电极出现缺陷。例如,正如观众LifeWalk指出的那样,在干燥过程中,阳极可能会分层成其组分材料。因此,对于单层层压,电池制造商通常会在电极上涂层50至80微米的活性材料。然而,特斯拉并不使用湿涂层技术。相反,他们使用干涂层工艺,将活性材料、聚合物粘合剂和导电碳粉混合成一种面团状物,然后利用热和压力将其层压到电流收集器上。

The dry coating process is able to laminate an ultra thick active material layer of up to 1 millimeter, which is over 10 times thicker than a typical wet coated electrode. In fact, Tesla's already using that advantage to coat their electrodes 50% thicker than the battery cells they purchase from, for example, LG Chem. But going even thicker might create challenges. Let's continue.
干式涂层工艺能够覆盖最厚可达1毫米的超厚活性材料层,这比通常湿法涂层电极的厚度要厚十倍以上。实际上,特斯拉已经利用这个优势,将他们的电极涂层厚度增加了50%,超过了他们从LG Chem等供应商购买的电池单元。然而,进一步增加厚度可能会面临一些挑战。接下来我们继续讨论。

The second reason why manufacturers don't laminate the electrode as thick as possible is because although making the active material thicker does increase energy density, it also reduces the charge and discharge rate of a battery cell. Just because a thicker active material layer slows down the flow of ions that occurs between the cathode and anode when the battery cell charges and discharges.
制造商之所以不把电极尽可能地厚度层压的第二个原因是,虽然增加活性物质的厚度可以增加电池的能量密度,但同时也会降低电池单元的充放电速率。这是因为更厚的活性物质层会减缓电池充放电时在阴极和阳极之间发生的离子流动。

So the choice comes down to thicker anodes that increase energy density versus thinner anodes that offer faster charge and discharge rates. This is where asymmetric lamination could help. Joe states that asymmetric lamination means making one side of the laminated material thicker than the other. If one side of the electrode foil is coated with active material much thicker than usual for increased energy and the other side is coated the same thickness or slightly thinner than usual for increased power, then the battery cell should, overall, have higher energy density while at the same time offering as good as or better charge and discharge rates.
因此,选择就在于增加能量密度的厚阳极与提供更快充放电速率的薄阳极之间。这就是不对称层压可以提供帮助的地方。乔解释称,不对称层压意味着使层压材料的一侧比另一侧更厚。如果电极箔的一侧涂上比通常更厚的活性材料以增加能量,而另一侧涂上与通常相同或稍微更薄的厚度以增加功率,那么电池单元的能量密度应该会更高,同时充放电速率也会与或优于通常情况相同。

The only catch would be that the thinner electrode facings that offer higher power density would probably only store about 25 to 30 percent of the battery's energy. That means, for example, if you charged a car that had a battery using an asymmetric electrode, the charge rate might be fast for the first 25 to 30 percent of the charge cycle and then slow down after that. But as those who own EVs know, that's already the case for every EV on the market. So asymmetric electrodes might just make that dynamic more pronounced.
唯一的问题可能是,提供更高功率密度的较薄的电极面可能只能储存电池能量的25%到30%。这意味着,例如,如果你给一辆使用不对称电极的电动汽车充电,充电速率在充电周期的前25%到30%可能会很快,然后在此之后慢下来。但正如那些拥有电动汽车的人所知道的,市场上每一辆电动汽车都存在这种情况。因此,不对称电极可能只是使这种动态变得更明显。

What about the claim in Joe's post that asymmetric lamination could contribute to a 10 to 20 percent energy density increase? As far as I can tell, that checks out, but it does require some clarification. First, the 10 to 20 percent increase also includes an upgrade to a higher energy density cathode material that uses more nickel, which would itself probably increase energy density by 3 percent. Second, generally, changes to the design of a battery cell are usually made incrementally. And so, something like a 7 percent energy density increase from asymmetric lamination would be more likely as a starting point. If we add the potential 3 percent from the cathode upgrade, that's about a 10 percent improvement. That is, I'm not expecting an imminent 20 percent energy density improvement, and the best case scenario in my view would be a 10 percent energy density improvement for this year. But that's the best case scenario. I'm not going to start building that into my assumptions and expectations yet. That's because there's been no confirmation that Tesla's actually pursuing asymmetric lamination. And it's a big departure from the way a battery cell is typically manufactured.
关于乔的帖子中关于非对称层压能否增加10%到20%的能量密度的说法呢?据我所知,这是成立的,但需要一些澄清。首先,这个10%到20%的提升也包括升级到使用更多镍的高能量密度正极材料,这本身可能会使能量密度增加3%。其次,一般来说,对电池单体设计的改变通常是逐步进行的。因此,从非对称层压中获得7%的能量密度增加更可能作为起点。如果我们再加上来自正极材料升级的潜在3%,那就是大约10%的改进。也就是说,我并不期望立即出现20%的能量密度改进,我认为今年最好的情况可能是10%的能量密度改进。但这只是最好的情况。我暂时不会把这种假设和期望加入我的考虑中。那是因为尚未确认特斯拉是否真的在追求非对称层压,而且这与典型电池单体的制造方式有很大的不同。

So for now, I'm sticking with my view from the Q3 earnings called that the third generation of the 4680 cell will hit at least 280 watt hours per kilogram with improvements to cell design and a better cathode, which is about a 5 percent increase. And that the fourth generation cell could hit at least 300 watt hours per kilogram with the addition of silicon to the anode, which is a 7 percent increase. I'd hope to see the third generation cell this year and the fourth generation cell next year. As usual, I'll be happy if I'm wrong.
就目前而言,我坚持我在第三季度收益报告中提到的观点,即改进电池设计和更好的阴极将使第三代4680电池每公斤功率至少达到280瓦时,提升约为5%。而第四代电池通过向阳极添加硅,每公斤功率至少可达到300瓦时,提升约为7%。我希望能在今年看到第三代电池的问世,并在明年看到第四代电池的推出。按照惯例,如果我错了,我会很开心。

If the asymmetric electrode rumor is true, it could both accelerate the increases in energy density and also raise the ceiling for what the 4680 is capable of. But improvements in battery technology often take longer than expected. So for now, I'm going to temper my expectations.
如果不对称电极的传闻成立,这可能会加速能量密度的增加,并提高4680电池的上限能力。但是,电池技术的改进往往比预期的时间更长。所以目前,我会保持对此的期望抱有一定的克制。

On that note, what could go wrong with asymmetric lamination or cause delays? There are dozens of possibilities, but let's look at the two that I think would most likely be raised in the comments. Cycle life issues and manufacturing challenges.
在这个问题上,不对称层压会出现什么问题或导致延迟呢?可能性有很多,但让我们来看看我认为最有可能在评论中提出的两个问题。寿命问题和制造挑战。

With regards to cycle life, the argument would be that having electrodes with such a great mismatch in thickness might cause unequal degradation that reduces cycle life. That's because most of the burst charge and discharge rates would be handled by the thinner electrodes. I'll explain why that is in more detail in a moment, but as I said earlier, a simple way to look at it is that the ions move more quickly through and between the thinner electrodes. Those increased charge and discharge rates would mean more electrochemical activity at the thinner electrodes and potentially all the degradation mechanisms that come with that, such as expansion and contraction, greater thermal stress, and more side reactions.
关于循环寿命的问题,可以认为,电极厚度差异巨大可能导致不均匀退化,从而降低循环寿命。这是因为大部分爆发充放电速率将由较薄的电极处理。我稍后会更详细地解释其中的原因,但正如我之前所说,简单来看,离子在较薄的电极之间移动更快。这增加的充放电速率意味着在较薄的电极上有更多电化学活动,潜在地引发膨胀和收缩、更大的热应力以及更多的副反应等退化机制。

However, from the little information I could find, it looks like the opposite might actually be true and that asymmetric electrodes can increase cycle life. Let's look at one example now from the perspective of mechanical stresses and another example later in the video from an electrochemical perspective.
然而,根据我所能找到的少量信息,事实似乎恰恰相反,即不对称电极可以增加循环寿命。现在让我们从机械应力的角度来看一个例子,稍后在视频中再从电化学的角度来看另一个例子。

With regards to mechanical stresses, this paper, titled, Asymmetric Electrode for suppressing swelling and commercial lithium-ion batteries, was shared with me by Pavon Srinivas and Daniel Rogstad of Freyr. The conclusion of the paper was that asymmetric lamination can be used to help direct expansion and contraction pressures within a battery cell as it charges and discharges. That helps reduce delamination and buckling during cycling, which improved the average cycle life of the battery cells that were tested as part of the research.
关于机械应力方面,这篇名为“用于抑制膨胀的不对称电极与商业锂离子电池”的论文是由Freyr公司的Pavon Srinivas和Daniel Rogstad与我共享的。该论文的结论是,不对称层压可以用来帮助引导电池在充放电过程中的膨胀和收缩压力。这有助于减少循环过程中的剥离和褶皱现象,并提高了作为研究的一部分进行测试的电池单元的平均循环寿命。

With that said, the paper only tested a maximum lamination thickness difference of 15%. Comping the thickness of one side of the electrode in a battery cell by 15% would probably only equate to an energy density improvement of at most 3%. That's because the active material on one side of the two double-sided electrodes makes up less than 20% of the weight of the battery cell, and 15% of 20% is 3%. That's a crude guess, but it serves the point. To get close to the 10% or more increase, Joe Tegmeyer shared, the difference in electrode thickness would have to be 50% to 100% or more. That means although the paper doesn't prove asymmetric coatings would improve the cycle life in the case of Tesla's potentially more extreme implementation, it looks promising based on the data we have so far.
话虽如此,该论文只测试了最大层压厚度差异达到15%的情况。将电池单体中电极一侧的厚度提高15%可能最多只会使能量密度提高3%。这是因为双面电极中的一侧活性材料仅占电池单体重量的不到20%,而20%的15%即为3%。这只是一个粗略的猜测,但它说明了问题。乔·泰格迈尔(Joe Tegmeyer)表示,要实现10%或更多的增长,电极厚度的差异必须达到50%至100%甚至更高。这意味着虽然该论文并未证明在特斯拉潜在更极端的实现中,不对称涂层能改善循环寿命,但根据我们目前掌握的数据,看起来很有希望。

The second thing that could go wrong with asymmetric lamination is that it could be difficult to manufacture. Part of the lamination process for Tesla's dry electrode manufacturing technique is calendaring, where the active material is compressed to the correct thickness and therefore porosity by rollers. Typically, when material with asymmetric coating passes through the rollers, each side of the material would be coated evenly and experience equal compression, which is of course the point with a symmetric electrode. If you put an asymmetric electrode through those rollers, it could, for example, cause one side of the coating to be compressed too much or not enough. I can think of a number of solutions to that, like adjusting the temperature of the roller on one side, or slightly changing the coating mixture on one side. But those are just guesses. Whatever the solution, it's an engineering challenge that would take a lot of trial and error to work through and implement on a full-scale production line. As always, I could be wrong here and it could be that asymmetric electrodes can be calendared identically to symmetric anodes and end up with ideal results. But significant changes to a manufacturing process are rarely that fortunate.
不对称层压的第二个问题是制造过程可能会很困难。特斯拉的干电极制造技术中,层压过程的一部分是压延,通过辊筒将活性材料压缩到正确的厚度和孔隙度。通常情况下,当带有不对称涂层的材料通过辊筒时,材料的每一侧都会被均匀涂层并经受相同的压缩,这当然是对称电极的目标。如果将不对称电极放入这些辊筒中,例如会导致涂层的一侧过度或不足压缩。对于这个问题,我可以想到一些解决方案,比如在一侧调整辊子的温度,或者微调一侧的涂层配方。但这些只是猜测。无论采取何种解决方案,都需要进行大量的试错与实践,才能在全面生产线上实施。像往常一样,我这里可能是错误的,不对称电极可能可以实现与对称阳极相同的压延效果,从而获得理想的结果。但对于制造过程的重大变化很少那么幸运。

Some might point out that Joe did say that Tesla's currently trialing asymmetric lamination. But in my view, that doesn't give us a solid clue on timing because it depends on whether the trials have just begun or whether they've been working the kinks out of the new lamination process on other equipment for months or years. The former could mean we won't see asymmetric electrodes for quite some time, and the latter could mean we see battery cells with asymmetric electrodes this year.
有人可能会指出Joe确实说了特斯拉正在进行非对称叠层试验。但在我看来,这并不能给我们一个确切的时间线线索,因为这取决于试验是刚刚开始,还是他们已经花了几个月甚至几年的时间来解决新叠层工艺的问题。如果是前者,意味着我们将在相当长时间内看不到非对称电极,而如果是后者,意味着我们可能今年就能看到具有非对称电极的电池。

As a final note, some people might be wondering if asymmetric electrodes would cause lithium plating issues or issues with the battery management system or BMS, which is the hardware and software that manages the battery cells. Lithium plating happens when too many lithium ions are shunted to the anode of the battery cell, and rather than entering the anode particles form pure lithium metal over the top of the anode particles. If that happens, it causes the battery cells to degrade more rapidly and can be a safety issue.
最后需要说明的是,有些人可能会想知道不对称电极是否会引起锂钝化问题或者与电池管理系统(BMS)有关的问题。电池管理系统是负责管理电池单元的硬件和软件。锂钝化会在电池单元的阳极上发生,当锂离子被过多地转移到阳极时,不会进入阳极颗粒,而是在阳极颗粒上方形成纯锂金属层。如果发生这种情况,将导致电池单元更快地降解,可能会引发安全问题。

That is, the thinking here would be that asymmetric lamination might cause lithium plating by driving uneven reactions throughout the battery cell. Similarly, uneven reactions throughout the battery cell might create challenges for the BMS. Surprisingly, in both cases, it doesn't appear that lithium plating would be more likely, nor would battery management be more difficult. Why is that? Let's take a look. Bear in mind, this is speculation based on chats with several battery scientists. So if you have a different view, let me know in the comments below.
也就是说,这里的思路是不对称的层压可能会通过在整个电池单元中引发不均匀的反应而导致锂齐膜。同样,整个电池单元中的不均匀反应可能给电池管理系统带来挑战。令人惊讶的是,在这两种情况下,锂齐膜似乎不太可能发生,并且电池管理也不会更加困难。为什么会这样呢?让我们来看一下。请注意,这是根据与几位电池科学家的对话推测出来的。因此,如果您有不同的看法,请在下方评论中告诉我。

A lithium-ion battery cell that has electrodes coated on each side is actually two cells in one. Looking at the image on screen, the first cell is formed across the inner separator between the outside of the anode on the left and the inside of the cathode on the right. The second battery cell is formed across the outer separator between the outside of the cathode, which spirals inward and puts it across from the inside of the anode on the left. The separators, of course, keep the two cells electrically isolated from each other.
在每一面都涂有电极的锂离子电池单元实际上是两个单元的结合体。观察屏幕上的图像,第一个单元跨越了位于左侧阳极外部和右侧阴极内部之间的内部隔膜。第二个电池单元则跨越了位于左侧阴极外部螺旋向内,并与内部阳极正好相对的外部隔膜。当然,这两个隔膜将两个电池单元从电学上隔离开来。

Then, the two electrode foils are joined at the top and bottom of the battery cell to form the positive and negative terminals. That creates a parallel circuit because the two positive foils and the two negative foils are joined.
然后,将两个电极箔在电池单元的顶部和底部连接在一起,形成正负极。这样就形成了一个并联电路,因为两个正极箔和两个负极箔被连接在一起。

The implications of that parallel circuit are that when the electrodes are laminated symmetrically, the two cells within the cell charge and discharge at a similar rate, because for the most part they're electrically identical. When the electrodes are laminated asymmetrically, the thinner electrode facings will have lower ionic resistance, which is due to the shorter average distance between the electrodes and because the ions have to travel through less material. That lower resistance means the chemical reactions will occur preferentially on the thinner electrodes and they'll charge and discharge first.
那种并联电路的含义是,当电极对称地层压在一起时,电池内的两个电池以类似的速率充电和放电,因为它们在很大程度上在电性上是相同的。当电极不对称地层压在一起时,较薄的电极面具有较低的离子阻抗,这是因为电极之间平均距离较短,并且离子需要穿过更少的材料。较低的阻抗意味着化学反应将优先发生在较薄的电极上,并且它们将首先充电和放电。

However, when the thinner electrode facings start becoming more fully charged or discharged, the voltage of the thin electrode pathway will increase or decrease as energy is stored or released. That in turn will drive more of the electrical load to the thicker electrode facings that are at a higher or lower voltage. That is, the electrochemical system within the battery cells is effectively self-balancing.
然而,当较薄的电极面逐渐充电或放电时,薄电极通道的电压将随着能量的储存或释放而增加或减少。这将驱动更多的电负载转移到电压较高或较低的较厚电极面上。也就是说,电池单元内的电化学系统在实际上是自平衡的。

Interestingly, that self-balancing function might also have an unexpected side benefit because the thinner electrode facings would have lower resistance and could absorb and release energy more quickly, they could react more quickly to current loads than the thicker electrode facings. That means in a sense, the thinner electrode facings could act as a filter because they could more easily absorb brief spikes in charge and discharge current, which would smooth the load for the less responsive thicker electrode facing and increase the overall life of the battery cell. This is much the same way that supercapacitors can be used to smooth the load on fuel cells, which extends their life by reducing degradation.
有趣的是,这种自平衡功能可能还会带来意想不到的附加好处,因为较薄的电极面可提供较低的电阻,并能更快地吸收和释放能量,所以它们可以比较快速地对电流负载做出反应,而较厚的电极面较慢。这意味着从某种意义上说,较薄的电极面可以起到一个过滤器的作用,因为它们可以更容易地吸收短暂的电荷和放电电流峰值,从而平稳负载压力,延长电池单元的整体寿命。这与超级电容器使用于平稳燃料电池负荷的方式非常相似,可以通过减少降解来延长其寿命。

Lastly, as far as the BMS is concerned, with an asymmetric coating the two battery cells within the cell are wired in parallel, which makes them one electronic unit. That means the BMS just sees one battery cell and monitors the voltage as it would with any other battery cell. Meanwhile, the asymmetric electrode self-balanced the entire battery cell through resistance and voltage.
最后,就电池管理系统(BMS)而言,如果应用不对称涂层,电池单体内的两个电池单元将并联连接,使它们成为一个电子单元。这意味着BMS只是看到一个电池单元,并像对待其他电池单元那样监测电压。同时,不对称电极通过电阻和电压实现了整个电池单元的自平衡。

In summary, it's not clear why there's so little research on asymmetric lamination for battery electrodes. It seems like a cheat code for improving the energy density of battery cells while maintaining power density. My best guess is that the wet process that's typically used to manufacture electrodes had limitations on how thick the active material could be coated reliably at high production rates, so making one side of the electrode coating 50 to 100% thicker wasn't explored as well as it could have been. Tesla's dry electrode coating, or lamination process, changes that by allowing for much thicker coatings at high production rates. If that's the case, then the 10 to 20% energy density increase rumor is definitely possible. However, again, I would caution that an innovation like this could take months or years to make it the full-scale production and could have drawbacks that my research didn't tease out. So until we hear more, I'm going to keep my estimates on the conservative side.
总结起来,关于电池电极的不对称层压研究为何如此有限还不是很清楚。它看起来像是一种秘诀,可以在保持功率密度的同时提高电池单元的能量密度。我最好的猜测是,通常用于制造电极的湿法工艺对在高速生产中可靠地涂覆活性材料的厚度有限制,因此将电极涂层的一侧增加50%至100%的厚度并未得到充分探讨。特斯拉的干法电极涂层或层压工艺改变了这一情况,可以在高速生产中实现更厚的涂层。如果是这样的话,那么有关能量密度增加10%至20%的传闻肯定是可能的。然而,我还是要提醒一下,像这样的创新可能需要几个月甚至几年才能实现大规模生产,并且可能存在我研究没有发现的缺点。因此,在我们听到更多消息之前,我会保持对其保守估计。

With that said, I'm increasingly bullish about the energy density of the 4680 in the long-term. Besides the clear pathway to higher energy density with a higher nickel cathode and higher silicon anode and the asymmetric lamination rumor we covered today, there's also the lithium doping patent I covered last year. As for the latter two, they're much easier to achieve with a dry coating process than with a wet coating process. So although the ramp of the dry coating process has been a challenge for Tesla, it does potentially open the door to the kind of energy densities that were suggested at battery day.
话虽如此,从长期来看,我对4680电池的能量密度越来越看好。除了通过使用更高镍正极、更高硅负极以及我们今天提到的不对称层压传闻来实现更高能量密度的明确途径之外,还有我去年报道的锂掺杂专利。至于后两者,通过干法涂层工艺比湿法涂层工艺更容易实现。因此,尽管对特斯拉来说,干法涂层工艺的推进一直是一项挑战,但它有可能打开电池日所提及的那种能量密度的大门。

As usual, I'll continue to keep you updated as we learn more. If you enjoyed this video, please consider supporting the channel by using the links in the description. Also consider following me on X. I often use X as a test bed for sharing ideas, and X subscribers like my Patreon supporters generally get access to my videos a week early. On that note, a special thanks to Phil Roberts and Rov of RCDIY, my YouTube members, X subscribers, and all the other patrons listed in the credits. I appreciate all of your support, and thanks for tuning in.
一如既往,我们在获得更多信息时会持续向您更新。如果您喜欢这个视频,请考虑通过描述中的链接来支持频道。同时,请考虑关注我的X主页。我经常将X作为一个测试平台来分享创意,而X的订阅者(例如我的Patreon赞助者)通常可以提前一周观看我的视频。 在此,特别感谢Phil Roberts和Rov of RCDIY,这个视频中的我的YouTube会员,X的订阅者,以及所有其他在片尾名单中列出的赞助者。我非常感谢您的支持,并感谢您的收看。



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