American scientists find a loss of lithium-ion battery life? Give me a break!

ଲେଖକ: ଆଇଫ୍ଲୋପାୱାର - Портативті электр станциясының жеткізушісі

Recently, the article called "American scientists find short reasons for the loss of lithium battery life", as a person in a lithium-ion battery industry, many years related experience tells me, a battery structure is different, the material is different, the conditions are different It will have a certain impact on battery life, so when someone asks for the reason for the lithium-ion battery life, Xiaobian has never given the answer directly, it must be asked to ask the battery system, after using the system and conditions to be cautious In-step, so when Xiaobian saw such a word, the article did a big fell eyeglass, scared Xiaobian quickly found this article to study carefully, but found this article thinking chaos, concept is unclear, helplessness Next, Xiaobian had to find the research results of "American scientists" mentioned in this article in "ScienceAdvance" journals. "American scientist" in online article named weizhang, how to listen to this is so familiar? Yes, this is the legendary Zhang Wei. The title of this article should be translated into "Lithium ion in the process of local concentration fluctuations in the process of embedding nanoparticles".

Through summary, we understand that this article is important to study the kinetic kinetics of nano-liFepo4 materials, and find that even Li + When embedded in nano LifePO4, the concentration distribution of Li + inside the nanoparticles is not uniform, and the local concentration of Li + in the nanoparticles also has fluctuations. Next, let's look at the views of the author want to express in the text. And there is also a phenomenon of local li concentration fluctuations.

So what is the use of this find? According to the author's explanation, this discovery will provide a new perspective for the study of microharitational research in mono-nanoparticles. Next, Xiaobian is briefly introduced the research results of weizhang. For a long time, due to the high residence of the closed structure and metal Li of the lithium-ion battery, it is very difficult to study the reaction kinetics of lithium ion batteries, so the experimental data on lithium-ion battery dynamics research is far behind theory.

Development speed. However, in recent years, the rapid development of the in situ observations allows us to track the reaction process within a single active material particles, the following figure shows the method for the author to observe the embedding reaction used in nano-LFP particles: 1) First, The authors prepare sheet-like single crystal LFP; 2), then assemble these sheet-like LFP materials on a mesh electrode for TEM observation; 3) Finally assembled to test batteries. By this method, the battery can be charged and discharged while the TEM observation.

WEIZHANG's research shows that during Lithium Lithium, it is not that the material we usually converts from the FP phase to the two phase reactions, and there is no obvious two-phase interface during the entire reaction, and the entire cyclizing process should be Solid resolution reaction process. The following dynamic diagram illustrates the change in Li concentration inside the Lithium process LLP crystal particles in the region of 3 * 3 nm2 (red represents a high Li concentration, blue represents a low Li concentration), and can be seen from the reaction process, start At the time, the local Li concentration was rapidly elevated (0.6-59s), and the LI concentration of the Li high concentration region began to decline, and finally fell to 0.

1 (at 121S), then the concentration of the overall Li was raised, reaching 0.7 (200S) ), Those who earliest to start the lithium, but in turn, finally completed the lithium. WEIZHANG Discovery When the research area further increases to 10 * 10 nm2, the magnitude of the concentration change in the particles will be greatly weakened, and the phenomenon of li concentration fluctuations is almost invisible when the research range is further raised to 20 * 20 nm2.

The fluctuations in LI concentration in LFP must be observed by means of high resolution methods, which is also observed in the past studies. Important contributions to this work of WEIZHANG still in the discovery of even in a single nanoparticle, there is still a phenomenon in which lithium lithium is uneven, and local still has a phenomenon of lithoscopic fluctuations, which is to study the lithium dynamics of LFP materials. The new perspective is supplied, but the author does not mention this uneven phenomenon and whether the lithium lithography will have a significant impact on the life of the lithium-ion battery.

Obviously, "American scientists find a loss of lithium battery life" This article describes the content of the original text, there is a suspicion of deliberate exaggeration, blonde eyeball. .