Marine lifepo4 lithium battery over discharge attention
Marine lifepo4 lithium battery over-discharge attention, because the overcharge of the lifepo4 lithium battery is easy to generate lithium dendrites at the positive electrode of the battery, and the piercing of the separator will cause the internal short circuit of the positive and negative electrodes of the battery, causing fire or explosion, so it is extremely important to protect the lifepo4 lithium battery from overcharge. . However, lifepo4 lithium battery is different from over-discharge. Since the battery energy is reduced during the over-discharge process, it will not cause accidents such as fire, but it will damage the battery cycle and life, so please pay attention to the following suggestions.
Battery Charge Vs Discharge And Why It Matters
1. Industry standard for over-discharge of marine lifepo4 lithium battery
At present, since lifepo4 lithium battery is widely used in the field of electric vehicles, the standard of lifepo4 lithium battery is mainly aimed at electric vehicles.
The ship lifepo4 lithium battery industry started late and lacks industry standards. The main performance and safety are based on the relevant standards of automobiles.
As far as overdischarge is concerned, electric vehicle batteries are more likely to have a certain depth of overdischarge under high-rate discharge conditions, so the requirements for discharge current are higher.
When the lifepo4 lithium battery is used as the power source of the ship, the ship is far less sensitive to the weight of the lifepo4 lithium battery than the car, and its endurance is the focus of the battery capacity design, which results in that the marine lithium battery does not require high power output, so The discharge rate requirement is not high.
Since pure battery-powered ships can only be charged after arriving in port, this can lead to a deep discharge depth of the battery cells in harsh conditions. To sum up, when the lifepo4 lithium battery is used as the power source of the ship, the discharge rate of the battery cell during the over-discharge process is not high, but the discharge depth may be large. The requirements of its over-discharge standards should be compatible with the over-discharge conditions that may occur during its use.
2. Several suggestions for over-discharge of marine lifepo4 lithium battery
(1) Due to the good ability of lifepo4 lithium battery to withstand over-discharge and the particularity of the ship being far away from the port, there may be a deep discharge depth, and its over-discharge depth should consider stricter requirements, requiring the battery SOC to complete the discharge. =-150%.
(2) Due to the low discharge rate of the actual marine battery cell, the overdischarge current can be considered to be the smaller value of 1C or the maximum discharge current specified by the Keheng lithium battery manufacturer.
(3) If the selected discharge current is less than 1C, the discharge time needs to be extended to ensure the depth of discharge. The actual discharge time is equal to the ratio of 1C to the actual discharge current multiplied by 90 minutes.