Full-Cell Builder

Choose a cathode and an anode to build a cell. The page balances their capacities with the N/P ratio and estimates the cell's voltage, capacity, energy and discharge curve at material level.

Battery type

Cathode

Lithium cobalt oxide · LiCoO₂ · ≈3.8 V · ≈140–150 mAh/g^{[32, 33, 34]}

Anode

Graphite · C₆ → LiC₆ · ≈0.1–0.2 V (staging plateaus) · ≈350–360 mAh/g^{[32, 42]}

N/P ratio (anode capacity ÷ cathode capacity)1.10

Average cell voltage≈3.70 VGraphite | LCO

Capacity≈101 mAh/gmAh per g of active material

Specific energy≈374 Wh/kgWh per kg of active material

Anode mass0.47 gper g of cathode · 32 % of the active material

How it is calculated

m_anode = N/P × Q_c ÷ Q_a = 1.10 × 148 ÷ 350 = 0.47 g
Q = Q_c ÷ (1 + m_anode) = 148 ÷ 1.47 = 101 mAh/g
V = V_c − V_a = 3.80 − 0.10 = 3.70 V
E = Q × V = 101 × 3.70 = 374 Wh/kg

Per 1 g of cathode. Q_c, Q_a: typical practical capacities (mAh/g). V_c, V_a: average potentials vs Li/Li⁺.

Discharge curve

Cell (cathode − anode)
Cathode LCO (vs Li/Li⁺)
Anode Graphite (vs Li/Li⁺)

Show the curve as a table

Discharged (%)	Capacity (mAh/g)	Cathode (V)	Anode (V)	Cell (V)
0	0	4.25	0.09	4.16
10	10	4.06	0.09	3.97
20	20	4.00	0.09	3.91
30	30	3.96	0.09	3.87
40	40	3.94	0.10	3.84
50	51	3.92	0.14	3.78
60	61	3.90	0.14	3.76
70	71	3.89	0.15	3.74
80	81	3.85	0.19	3.66
90	91	3.77	0.22	3.56
100	101	3.00	0.80	2.20

Material-level estimate. Capacities and average voltages are the typical literature values from the electrode materials page; real cells are lower because current collectors, separator, electrolyte and casing add mass without storing charge. The curve shapes are schematic, at a slow rate with no polarization, and losses such as the lithium consumed by the SEI on the first cycle are ignored.

Why the N/P ratio matters

N/P is the anode's capacity divided by the cathode's. It affects both the energy density and the long-term performance of a cell^[50]. All the cyclable lithium comes from the cathode, so with N/P above 1 the anode is never completely filled at the end of charge: its spare capacity stays unused at the fully lithiated end, close to 0 V, where lithium plating can occur^[54]. The price is extra anode mass, which lowers the capacity and energy per gram: move the slider to see it.

Sources: [32] Nitta et al. (2015) · [33] Mizushima et al. (1980) · [34] Lin et al. (2012) · [42] Dahn et al. (1991) · [50] Luo et al. (2022) · [54] Waldmann et al. (2018)