◆Hka hta rawng ai electrolyte ni gaw hpa ni rai kun?
◆N-gun ja ai Electrolyte ni hpe hpaw tsun dan ai
Dai electrolyte gaw, n mai garan kachyan ai arung arai langai rai nga ai.lithium-ion wan jak ni, gaw battery a charge-n-gun shayawm ai aten hta ahkyak ai shara hpe hkam la nga ai.
Lithium ions ni hpe atsawm sha htaw sa ai lam hte n-gun hpe htawt sit ai lam hta lit nga ai sha n-ga, positive hte negative electrode lapran direct electron lwi ai hpe atsawm sha pat shingdang lu ai electronic insulation atsam ni hpe mung lu da ai. Ga shadawn hku tsun ga nga yang, dai electrolyte gaw lithium-ion battery kata na "sai" zawn rai nna, kaja ai hte n kaja ai electrode arung arai ni a lapran matut mahkai lam hpe madi shadaw ya ai, dai hku nna charge-discharge galaw ai lam yawng hpe hkrak hkra galaw ya lu ai.
Lithium-ion battery a matu kaja dik ai electrolyte gaw lawu na ra kadawn ai lam manga hpe hkan sa ra ai:
(1) High ionic conductivity (>10⁻3S/cm).
(2) Wide electrochemical window (>4.5 V hte Li+/Li).
(3) Electrode ni hte kaja ai hku htuk manu ai, mai byin ai daram npu na interfacial n-gun hpe n-gun jaw ai.
(4) Katsi ai nbung hte chemical stability a majaw, battery hpe nbung katsi ai shara law law hta shim lum ai hku bungli galaw lu ai.
(5) Manu n law ai, n hkru n kaja ai lam n law ai, grup yin hpe mung n hkra ai.
Battery n-gun n-gun hte n-gun n-gun hpe ra sharawng ai lam ni law wa ai hte maren, battery hpaji masa mung lawan ladan rawt jat wa nga ai, electrode arung arai ni mung grai rawt jat wa sai. Dai hte nhtan shai ai hku nna, electrolyte system ni hpe galaw shapraw ai lam hta hpang hkrat mat sai. Ya aten hta, lithium-ion battery n-gun dat ni hpe gyin shalat ai lam hpe, n--hka n-re ai n-gun dat, hka n-gun dat, hte n-gun ja ai-state n-gun dat ngu ai masum hku nna, galu kaba ai hku garan ginhka mai nga ai.
-hka n re ai hka n-gun dat
Lithium-ion battery ni hta lawm ai n--hka n lawm ai hka n-gun rawng ai electrolyte ni gaw hka n lawm ai electrolyte system ni hpe tsun mayu ai rai nna, madung hku nna hka n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai n-gun rawng ai lam ni hpe tsun mayu ai. Ndai n-hka n lawm ai hka htung ni gaw, hka hpe electrolysis galaw ai (sh) electrode arung arai ni hte n kaja ai hku byin wa ai lam ni hpe koi lu na matu, hka htung n re ai sha, organic hka htung ni rai nga ai. Lithium sau ni gaw lithium-ion htaw sa na matu madung htaw sa ai ni rai nna, hka ja ai baw ni gaw lithium sau ni hpe garan kachyan ai, garan kachyan ai, madi shadaw ya ai hku nna magam gun nga ai, additives ni gaw lithium-ion battery ni a electrochemical bungli galaw ai lam (sh) shim lum lam hpe grau kaja hkra galaw ya ai.
Lithium-ion battery ni hta lang ai hpaga lam hta lu mai ai wan n-gun (dai gaw, ntsin wan n-gun) ni gaw, madung hku nna, lithium ntsin langai (sh) law law hpe organic ntsin lahkawng (sh) law law hta garan nna hpaw da ai; n-gun langai hte hpawng de da ai electrolytes ni gaw grai n law ai. Solvent law law lang ai a lam gaw, tengman ai-mungkan battery ni hta n bung ai, nhtan shai ai pyi, ra kadawn ai lam ni nga ai majaw, solvent langai hpe lang nna galaw na matu yak hkak ai. Ga shadawn, electrolytes ni gaw, n-gun ja ai n-gun ra ai sha n-ga, dielectric constant mung grai law ai; dai majaw, n bung ai physicochemical arawn alai ni lawm ai solvent ni hpe kayau kaya lang nna, n bung ai arawn alai ni hpe kalang ta madun dan ai. Dai hta n-ga, lithium sau ni hpe lata ai lam n law ai majaw, shanhte a akyu ara ni hpe mung loi loi hte n mu lu ai majaw, madung hku nna kalang ta n lang ai.
Kaja dik ai organic hka ja ai baw ni gaw lawu na ahkyak ai atsam marai ni hpe hkam la ra ai: Langai, shanhte gaw lithium sau ni hpe kaja ai hku hka ja lu na matu dielectric constant kaba ra ai; lahkawng, shanhte gaw n-gun n law ai melting point hte boiling point kaba ai rai nna, electrolyte a bungli galaw ai nbung n-gun hpe grau dam lada hkra galaw ra ai; masum, n-gun n law ai gaw, n-gun n law ai lithium ions ni hpe n-gun jaw ya ai; hte hpang jahtum, ndai hka ja ai tsi ni gaw manu n-htuk ai hte n-gun n law ai (kaja dik htum gaw non-toxic) rai ra ai. Carbonate n-gun dat ni gaw, lithium-ion battery hpaga lam hta shawng nnan lang lang ai hte grau nna jai lang ai organic n-gun dat langai mi hku nna, battery n-gun dat ni a lam hta ahkyak ai shara hpe hkam la nga ai.
Ya aten hta ndai zawn re ai solvent hta madung hku nna structural hkrang lahkawng lawm ai: cyclic hte chain. Lawu na table hta, law malawng lang ai n--hka n lawm ai hka htung, electrolyte, hte organic hka htung law law a seng ang ai hkum hkrang masa ni hpe kadun dawk tsun da ai.
| Pang | Hpan | Hkrang | Hka lim ai shara (degree) | Hka lum ai shara (degree) | Langai hkrai a nbung n-gun (25 degree) | Hkrum shaga ai n-gun (25 degree)/(mPa·s) |
|---|---|---|---|---|---|---|
| Ethylene Kabonat (EC) | Cyclic | 36.4 | 248 | 89,780 | 1.904 (degri 40) | |
| Hpyen n-gun (PC) | Cyclic | -48.4 | 242 | 64,920 | 2.53 | |
| Kabonat | Butilen Kabonat (BC) | Cyclic | -54.0 | 240 | 53,000 | 3.20 |
| Dimethyl n-gun (DMC) | Linear | 4.6 | 91 | 3,107 | 0.59 | |
| Dietyl Kabonat (DEC) | Linear | -74.3 | 126 | 2,805 | 0.75 | |
| Ethyl Methyl Karbonat (EMC) | Linear | -53.0 | 110 | 2,958 | 0.65 |
Ya aten hta, alkyl carbonate ngu ai ntsin hpe wan n-gun hta grai lang nga ai. Ndai solvent ni gaw oxidation hpe ninghkap lu ai atsam kaja nga ai rai nna, voltage kaba ai masa hta grai kaja ai ngang grin ai lam hpe madun dan lu ai. Ethylene carbonate hte propylene carbonate zawn re ai cyclic carbonate ni gaw, shanhte a dielectric n-gun grai law ai majaw chye ai, lachyum gaw, lithium sau ni hpe grau kaja hkra hka ja lu ai; rai tim, n-gun ja ai intermolecular n-gun ni a majaw, ndai solvent ni gaw viscosity grai law ai majaw, shanhte kata na lithium ions ni a shamu shamawt ai lam hpe shayawm kau ya ai. Dai hte nhtan shai ai hku nna, dimethyl carbonate hte diethyl carbonate zawn re ai chain carbonate ni gaw, n-gun n law ai raitim, dielectric n-gun n law ai majaw, lithium sau ni a matu n-gun n law ai hka lim ai lam hpe byin shangun ai. Dai majaw, grau kaja ai ionic conductivity hte hka htung ni hpe hkyen lajang na matu, PC+DEC (sh) EC+DMC kayau ai zawn re ai hka htung amyu myu hpe kayau kaya galaw chye ai. Lithium sau ni gaw, electrolyte kata na lithium ion ni a npawt nhpang hku nna, lithium-ion battery ni hpe charge galaw ai hte n-gun dat ai shaloi, lithium-ion ion ni hpe htawt sit ai hta ahkyak ai lit nga ai. Shanhte a bungli galaw ai lam gaw lithium-ion battery ni a lam law law hpe hkrak hkra machyi shangun ai, dai hta n-gun n-gun, n-gun n-gun, bungli galaw ai voltage n-gun, cycle prat, shim lum lam ni lawm ai. Ya aten hta, laboratory sawk sagawn ai lam hte hpaga lam hta, anionic radii kaba ai hte redox n-gun ja ai lithium sau ni hpe laksan lata la ma ai. Shanhte a chemical nsam hpe madung tawn nna, lithium sau ni hpe n-gun n rawng ai lithium sau hte organic lithium sau ngu nna, n-gun kaba ai hku garan ginhka mai ai. LiPF6, LiClO4, LIBF, LIASF ni lawm ai n-gun n rawng ai lithium sau law law hpe galaw shapraw da sai. Dai hte nhtan shai ai hku nna, lithium-ion battery ni hta lang ai organic lithium sau ni hpe ndai n-hprang n-gun n-rawng ai lithium sau ni a anion ni hta electron-shaw la ai hpung ni hpe jat bang nna galaw shapraw ai, dai ni gaw lithium dioxalato-borate (LiBOB), lithium difluo{0o{xala{i Lawu na table hta, lithium-ion battery ni hta lang ai lithium sau law law a, seng ang ai physicochemical atsam ni hpe madun da ai.
| Pang | Lithium ntsin | Molecular n-gun (g/mol) | Carbonate ni hta lwi ai kun? | Hka hta lwi ai kun? | Wan n-gun htawt sit lu ai atsam (1 mol/L, EC/DMC,℃20) (mS/cm) |
|---|---|---|---|---|---|
| N-gun n rawng ai Lithium sau ni | LiPF6 | 151.91 | Mai sa | Mai sa | 10.00 |
| LiBF4 | 93.74 | Mai sa | Mai sa | 4.50 | |
| LiClO4 | 106.40 | Mai sa | Mai sa | 9.00 | |
| Organic Lithium sau ni | LiTFSI | 287.08 | Mai sa | Mai sa | 6.18 |
| LiFSI | 187.07 | Mai sa | Mai sa | 10.40 | |
| LiBOB | 193.79 | Mai sa | Mai sa | 0.65 |
Additives ngu ai gaw, n-gun n law ai (mass by 10% hta n jan ai) hta electrolyte hta bang da ai arung arai ni rai nna, dai ni gaw, laksan bungli galaw ai lam ni nga ai rai nna, battery a electrochemical arawn alai ni hpe grai shatsaw ya lu ai. Shanhte a bungli ni hpe madung tawn nna, ndai additives ni hpe law law hku nna garan ginhka mai ai: film-forming additives, wan hkru ai lam hpe pat shingdang ai additives, hte additives ni hpe grai law hkra n-gun n-jaw hkra galaw ai. Dai hta n-ga, n-gun n-gun hpe jat ya na matu, n-gun n law ai-katsi ai masa hta bungli galaw ai lam hpe grau kaja hkra galaw na matu, shing nrai, electrolyte ntsin hta n-gun n-gun hte HF n-gun hpe hkang lu na matu lang ai additives ni nga ai.