Lithium iron phosphate battery pack is favored by many fans because of its lighter weight under the same capacity, the capacity of lithium battery is one of the important performance indicators to measure the performance of the battery, when discharging, the voltage of lithium battery will gradually decrease with the passage of power, and there is a considerable slope.This paper will solve the mystery of the voltage and capacity of the lithium iron phosphate battery pack.
1) Lithium iron phosphate battery pack capacity:
Lithium battery pack capacity is one of the important performance indicators to measure the performance of the battery, it indicates the power released by the battery under certain conditions (discharge rate, temperature, termination voltage, etc.) (can use JS-150D for discharge test), that is, the capacity of the battery, usually in hours.The capacity of lithium battery is divided into actual capacity, theoretical capacity and rated capacity according to different conditions. The calculation formula of battery capacity C is C= t0It1dt, and the battery is divided into positive and negative electrodes.

2) Voltage of lithium iron phosphate battery:

Lithium iron phosphate battery refers to a lithium-ion battery using lithium iron phosphate as a cathode material.The cathode materials of lithium ion battery mainly include lithium cobalt oxide, lithium manganese oxide, lithium nickel acid, ternary materials, lithium iron phosphate and so on.
The charging voltage of lithium iron phosphate battery pack should be set at 3.65v, nominal voltage 3.2v, the maximum charging voltage can be 20% higher than the nominal voltage, but the voltage is too high to damage the battery, 3.6v voltage is lower than this index, no overcharge.Lithium battery pack if set the minimum 3.0v need to charge, then 3.4v than the minimum 0.4v, 0.6v than 0.6 v can release half of the power, that is to say, every charge, more than 3.4v use time, because the battery use times, so life increased by half, so in the case of not damage the battery, increase charging voltage, will increase the lithium battery life.

3) What is the relationship between the pack voltage and the capacity of the lithium iron phosphate battery pack?
Generally speaking, the higher the charge and discharge voltage of the lithium iron phosphate battery pack, the greater its capacity.The charging and discharge voltage of lithium batteries of different materials is different, and the lowest is the lithium iron phosphate battery.As the capacity decreases, the voltage decreases, and the capacity is small when the voltage is below the rating.
1. For the same battery, with the same residual capacity, the voltage value varies due to the size of the discharge current.The higher the discharge current, the lower the voltage.In the absence of a current current, the highest voltage is present.
2. The impact of ambient temperature on the lithium battery pack voltage. The lower the temperature, the lower the battery voltage of the same capacity.
3. The impact of the cycle on the battery discharge platform. As the cycle proceeds, the discharge platform of the lithium-ion battery tends to deteriorate.The discharge platform decreases.So the capacity represented by the same voltage also changes accordingly.
4. Different manufacturers, different capacity of lithium ion batteries, their slightly different discharge platforms.
5. The discharge platform of different types of electrode materials is quite different.The lithium cobalt and manganese lithium discharge platforms are completely different.
All these will cause voltage fluctuations and voltage differences, making the capacity of the lithium iron phosphate battery pack display unstable.

Lithium battery capacity refers to the size of the battery storage power.The voltage of lithium iron phosphate battery pack has been decreasing during the discharge process, such as the battery 3.6v, 19ah, 19ah capacity is not put to 0v, but 2. several or 3. When, the discharge capacity is 19ah, if put to 0v, the capacity will be a little more than 19, too put, will damage the life of the battery.

100%—-4.20V100%—-4.20V
90%—–4.06V90%—–3.97V
80%—–3.98V80%—–3.87V
70%—–3.92V70%—–3.79V
60%—–3.87V60%—–3.73V
50%—–3.82V50%—–3.68V
40%—–3.79V40%—–3.65V
30%—–3.77V30%—–3.62V
20%—–3.74V20%—–3.58V
10%—–3.68V10%—–3.51V
5%——3.45V5%——3.42V
0%——3.00V0%——3.00V

The above is the relationship between the lithium iron phosphate battery pack voltage and capacity, in the absence of current, the voltage is the highest, the lower the temperature, the lower the voltage of the same capacity of lithium battery.Generally speaking, the higher the charge and discharge voltage of lithium iron phosphate batteries, the greater its capacity.