C-stopnja se nanaša na razmerje med vrednostjo toka polnjenja/praznjenja in nazivno zmogljivostjo baterije.

C-stopnja litij-ionske baterije določa, kako hitro se lahko baterija popolnoma napolni ali kako hitro se lahko popolnoma izprazni. S poznavanjem stopnje C, ljudje lahko ugotovijo, da je hitrost polnjenja ali praznjenja baterije hitra ali počasna.

Za primer vzemimo 2000 mAh litij-ionsko baterijo. Njegova nazivna zmogljivost je 2000 mAh.

Če je tok praznjenja 2000mA, bo zahtevalo 1 uro, da se popolnoma izprazni, potem je stopnja C 1C.

Če je tok praznjenja 4000mA, potem bo zahtevalo 0.5 ure, da se popolnoma izprazni, in stopnja C je 2C (4000mA/2000mA=2C)

Če je tok praznjenja 400mA, potem bo zahtevalo 5 ure, da se popolnoma izprazni, C-stopnja pa je 0,2C (400mA/2000mA=0,2C)

Tukaj je formula, da bo bolj jasno:

D-stopnja (C) = Tok polnjenja/praznjenja(A)÷ Nazivna zmogljivost(ah)

When discharging with N times the current of the 1C capacity of the lithium battery, and its discharge capacity is more than 85% of the 1C capacity of the battery, we consider the discharge rate of the battery to be N times.

The C-rate of a battery is an important consideration when designing a charge or discharge system because it affects the battery’s performance and lifetime.

Na primer, charging or discharging a battery at a high C rate will cause the battery to heat up and degrade faster, while charging or discharging at a low C rate can extend the life of the battery, but will take more time.

Trenutno, the charging rate supported by lithium batteries is only 1.3C. V nasprotju s tem, graphene fast charging batteries have 6C fast charging capabilities and can be charged to 85% in 8 minut, which is equivalent to the time it takes to fill up a tank of fuel for a fuel vehicle.

Na splošno, we call a lithium battery discharged at 1C a standard battery, a lithium battery discharged at 2C-10C a low-rate battery, and a lithium battery discharged over 10C a high-rate battery.

Lithium batteries are used in different products depending on the rate.

The high rate of the lithium battery is relative to the ordinary rate, representing the charge and discharge capacity of the lithium-ion polymer battery.

If an ordinary battery is charged quickly, it is easy to cause lithium precipitation at the negative electrode, resulting in accelerated performance degradation of the lithium battery. In severe cases, it may cause a short circuit inside the battery, causing a fire and explosion.

Učinkovitost hitrosti polnjenja in praznjenja litijevih baterij je neposredno povezana s sposobnostjo migracije litijevih ionov na pozitivni in negativni elektrodi, elektrolit, in vmesnik med njimi. Vsi dejavniki, ki vplivajo na hitrost migracije litijevih ionov (ti vplivni dejavniki so lahko enakovredni tudi notranjemu uporu baterije), bo vplivalo na hitrost polnjenja in praznjenja litij-ionskih baterij.