N/P ratio (Negative/Positive) is in the same stage and under the same conditions, the capacity of the negative electrode on the opposite side exceeds the capacity of the positive electrode. In fact, there is another saying called CB, which is one of the important factors affecting the deep cycle battery. one. Therefore, N/P should be considered in the design. This includes:

   First, the first effect: it is necessary to consider all the substances that react, including conductive agents, adhesives, current collectors, diaphragms, and electrolytes. But the gram capacity data we get from material suppliers often only look at the half-electric gram capacity of the active material, which is why the actual full battery gram capacity differs from the design gram capacity.

   Second, the assembly process: there is a difference in the design of the N/P ratio between the cylindrical battery and the square battery, which is mainly caused by the tightness of the contact between the positive and negative plates. The combination of powder and current collector is also considered to be an assembly. The direct contact between powder and current collector and the contact between powders are also one of the factors that affect the gram capacity and thus the N/P ratio.

   Third, the formation process: the formation process is different, which also has an impact on the N/P ratio. The formation process also affects the first effect by affecting the gram capacity.

   Fourth, cycle: cycle life is one of the most important indicators to measure battery performance. If the positive electrode decays quickly, the N/P ratio is lower than the design, so that the positive electrode is in a shallow charge-discharge state. On the contrary, if the negative electrode decays quickly, the N/P ratio is higher, and the negative electrode is in a shallow charge-discharge state.

   Fifth, safety: safety is a more important indicator than circulation. Not only does it have an impact on the safety performance of the finished product, but some pre-charged cells have lithium-depositing and heat-generating cells. We need to review whether there are design problems.