Voltage delay or passivation Phenomenon of Lithium LiSOCL2 battery
Voltage delay or passivation Phenomenon of Lithium LiSOCL2 battery
The lithium thionyl chloride Battery, also known as the Li/SOCl2 Battery, ER Battery or Li-SOCL2 battery, is one of the highest energy density battery in the range of practical applications. It is non-rechargeable battery at a voltage of 3.6 V and has a specific energy of 590 W · h/kg and 1,100 watt-hours per cubic centimeter. The outstanding feature is large capacity and low discharge rate.
Long storage life is the benefit of ER battery. as other batteries, the ER battery still have self-discharge, just the self-discharge rate is very low. which make sure it can be stored more than 10 years. Why is that?
4Li+2SOCl2→4LiCl+S↓+SO2
Because lithium chloride film membrane ( LiCL )will appear when a long storage comes,which slow down the chemical reaction.
Each coin has two sides, lithium chloride film membrane also has advantage and disadvantage. It is good for low self-discharge rate,but it will make load voltage delay, that is passivation Phenomenon.
That is to say: the voltage delay after long storage is a character of LiSOCL2 battery,the passivation after storage comes from lithium chloride film membrane,which slow down the chemical reaction. as the other side, the file membrane also make sure the battery have low self-discharge rate, long storage life. when you use them after long storage over 45 days, the voltage will recovery as before after few seconds.
Passivation degree and performance on pulse load after long storage depenps on many factors, such as storage time, storage temperature,discharge current,etc. The passivation film develops fast as temperature rise, 23+/-2℃ is best for storage. and the Passivation membrance grows fast in the first 1~2 years, when it reachs a certain thickness, grows slow.
By the way, the shelf-life means you store SER Li-socl2 Battery cells in warehouse for over 10 years, the batteries are still alive; while service time is runing time, and its duration depands on the comsuming current (please consult the customer for that) and batteries' capacity.
Next article will tell you: How to deal with the problem?
