What Exactly Is Battery Thermal Management? What Is Its Significance?

As the name suggests, thermal management of battery packs is a technology to control the temperature of power batteries in new energy vehicles.

 

1. Where Does The Heat Of Thermal Management Come From?

The biggest difference between new energy vehicles and traditional vehicles comes from the source of capacity energy, new energy vehicles, especially pure electric vehicles, rely on the power battery's energy storage to provide the power energy, in the process of providing energy storage, it will actually generate a lot of heat, for example:

1.1 Power battery charging and discharging process, internal electrochemical reactions, charging heat absorption, discharge heat dissipation, these reactions will bring heat to the battery pack.

1.2 Heat is generated when the current flows on the internal resistance of the battery, this heat is the most frequent way of generating heat in the battery.

1.3 The decomposition of electrolytes and other materials when the power battery is exposed to high external temperatures, or overcharged, or over-discharged, or even crushed, etc., will also generate heat.

Therefore, after the heat of the battery is generated, if we don't control it, the electric cell will easily overheat, which will affect the safety of the power battery. Therefore, we have to maintain the temperature of the power battery in various ways.

Here, in fact, thermal management is not just to dissipate the temperature of the power battery, when it is cold, heating the power battery is also an important requirement, because the power battery actually has a certain operating temperature range, once beyond that range, the battery capacity and charging and discharging performance will be affected, so, in the case of cold, thermal management is also needed to heat the battery pack.

 

2. What Are The Ways Of Thermal Management?

2.1 Air Cooling
This is simple, in fact, by blowing the way to the battery cooling, as far as the current situation, the air cooling system is to install a fan near the battery pack, and the formation of air convection conditions, through the airflow to take the heat away, this way is simple and rough, low cost, the effect is general, especially in this mode, the winter can not be heated to the vehicle, so that the quality of the experience is reduced.

2.2 Liquid cooling (heat)
At this stage, liquid cooling is through the electric core and close to the region of the water flow in the pipeline to form a flow, taking away the heat on the wall of the pipeline, so that the temperature of the vehicle gradually goes to cool down. The principle is actually similar to the bath when you take a shower when you are hot so that the water flow takes away the temperature of the body.

2.3 PTC heating
The principle of heating is also very simple, similar to the electric blanket we sleep on in winter, under a heating film with resistance wire, and insulation-wrapped film made of heating film, and then laid on the shell of the core module, when you need to heat up, power on the core can be heated up. TKT's BCS series BTMS system is the use of PTC heating, to ensure that the battery's long-lasting and stable performance.

 

3. What Is The Significance Of Thermal Management?

It is very simple, the role of thermal management is to control the above-mentioned means, how to ensure that the battery pack is in the safe operating range, does not have problems, to ensure driving safety, and maximize performance. Let's take an example to make it more graphic:

3.1 Wake up in the morning, enter the car, the car hair commonly used drivers come up, start to heat the water in the pipeline to provide as much heat as possible for the battery to activate the battery properties, to avoid the day is too cold, there is no equipment.

3.2 Avoid unsuitable initiatives such as incorrect charging, for example, during charging, the temperature of the battery pack rises, and at this time the thermal management system will ask for cold water to be fed in, to flow through that heat, to take the heat away, and to ensure that the host is safe.

3.3 Increase performance, similar to the ZhiJi L7 can be continuous ten times the limit of charging and discharging, which is also a case of better heat dissipation of the motor. Another example is that the charging efficiency at -20℃ is only 65% of that at 15℃. When driving an electric car, you will feel that the range becomes shorter at low temperatures for what seems to be about the same amount of power. If the battery cell can be warmed up by heating, the range will be restored.

In short, the battery thermal management device serves the battery: days cold "clothing" heating, days hot "fan" cooling, and strives to create the best working conditions for the battery. For more information on Battery Thermal Management Systems or products, please feel free to contact TKT HVAC, which offers a full range of BTMS product solutions and services.