Nuacht Tionscail

Cadhnraí litiam-ian ardfhuinnimh a fheabhsú le filler carbóin

2021-07-22


Leictreoidí tiubha le nanaibeadáin charbóin aon-ballaí (SWCNTanna) do chórais stórála fuinnimh inscálaithe. Creidmheas: Zhengyu Ju agus Guihua Yu

 

Is iad cadhnraí litiam-ian an phríomhfhoinse cumhachta in-athluchtaithe do go leor gairis iniompartha chomh maith le feithiclí leictreacha, ach tá a n-úsáid teoranta, toisc nach soláthraíonn siad aschur ardchumhachta agus iad ag ligean stóráil fuinnimh inchúlaithe ag an am céanna. Tá sé mar aidhm ag taighde a tuairiscíodh in Athbhreithnithe ar Fhisic Fheidhmeach réiteach a thairiscint trína thaispeáint conas a fheabhsaíonn cuimsiú líontóirí seoltaí feidhmíocht ceallraí.

 

Tá an dearadh ceallraí is fearr i gceist go tiubhleictreoidstruchtúir. Feabhsaíonn sé seo andlús fuinnimh, but the design suffers from poor lithium-ion transport, a key step in the functioning of these leictreoids. Various improvement techniques have been tried, including building vertically aligned channels or creating pores of the proper size to facilitate transport of the lithium ions.

 

Cur chuige eile is ea líontóirí a úsáid as carbón a sheolann leictreachas. Bhreithnigh an staidéar seo trí chineál líontóirí: nanaibubáin charbóin aon-ballaí (SWCNTanna), nana-bhileoga graphene, agus substaint ar a dtugtar Super P, cineál cáithníní dubh carbóin a tháirgtear le linn ocsaídiú réamhtheachtaithe peitriliam. Is é Super P an filler seoltaí is coitianta a úsáidtear icadhnraí litiam-ian.

 

The fillers were added to a type of leictreoid material known as NCM that contains nickel, cobalt, and manganese. The investigators examined the resulting composites with scanning electron microscopy. The Super P and NCM particles were found to be arranged in a point-to-point contact mode.

 

Bhí na SWCNTanna fillte, áfach, timpeall na gcáithníní NCM, ag cruthú sciath seoltaí. Ina theannta sin, breathnaíodh líonraí de SWCNTanna idirnasctha sna spásanna idir cáithníní NCM. Tá annana-bhileoga graphene were also wrapped around the NCM leictreoid particles but not as uniformly as the SWCNTs were.

 

The SWCNTs were found to be the best conductive filler for NCM leictreoids.

 

"Tá an seoltacht tomhaiste comhsheasmhach le teoiric síothlaithe ... Nuair a chuirtear filler seoltaí leictreach le maitrís inslithe, tarlóidh méaduithe suntasacha ar an seoltacht a luaithe a fhoirmítear an chéad chonair seolta tríd an gcomhdhúil," a dúirt Guihua Yu, duine de na húdair .

 

Since percolation requires a complete pathway through the filler, a sufficient amount of conductive filler is needed. Therefore, the investigators considered various amounts of filler and found that combining NCM leictreoids with as little as 0.16% by weight of SWCNT produced good electrical conductivity. Higher amounts of Super P and graphene were required to achieve these same results.

 

D'úsáid na himscrúdaitheoirí roinnt teicnící speictreascópacha, lena n-áirítear speictreascópacht ionsúcháin Raman agus X-gha, chun staidéar a dhéanamh ar na comhdhúile a bhí mar thoradh orthu.

 

"This is a collaborative effort from the Center for Mesoscale Transport Properties, an Energy Frontier Research Center supported by the U.S. Department of Energy Basic Energy Sciences program. Our findings suggest that the integration of SWCNTs into the NCM leictreoid facilitate ion and charge transfer. This will lead to higher electrochemical utilization, especially at high rates of discharge," Yu said.