Many years ago, we saw a statement on social platforms that a mobile phone manufacturer had developed a technology of "generating electricity based on chip waste heat".
According to the relevant descriptions at the time, this technology was attached to the SoC by a special power generation chip, which could directly "absorb" the heat of the SoC and convert it into electricity. In this way, it can not only replenish the power of the mobile phone, but also play a role in cooling the chip in disguise.
As far as we can remember, this kind of publicity attracted some attention at the time, but it quickly disappeared, and no related products were mass-produced or marketed in the future.
The technology actually exists, but mass production is almost impossible
In fact, this method of "absorbing" and converting the waste heat of the chip into electrical energy does exist.
To put it simply, it is the use of the characteristics of some special materials in the process of heating and cooling the physical properties will change, so that they first absorb heat and deform, and then depart from the heat source because of deformation, and then cool down to return to the original shape. In this cycle, this movement can be applied to the classic generator structure, which generates electrical energy. In fact, this is the basic principle of heat pump power generation that everyone knows.
Heat pump power generation, we have to think about how to miniaturize (the picture shows the on-board heat pump equipment)
Of course, heat pumps also have an obvious disadvantage, that is, if you want to stuff it into a device as small as a mobile phone, it will involve the miniaturization of the mechanical structure of the generator (and the thermally expanded parts), which is basically impossible to solve with current material technology. So this is the fundamental reason why the "endothermic power generation design" described at the beginning of this article is difficult to actually mass-produce.
Without the need for mechanical structures, thermoelectrochemical cells offer new hope
However, with the advancement of technology, it seems that new solutions are now being ushered in. According to a recent study released by the University of Utah, the team has invented a new heat-absorbing power generation device based on a "thermoelectrochemical cell".
According to the relevant information, there is no mechanical structure inside the thermoelectrochemical battery, and it purely relies on the compound to realize the conversion of heat energy to electric potential energy. Therefore, the volume can be made very slim. The current version of a thermoelectrochemical cell with an area of about 1 square centimeter is said to produce about 0.001 watt-hours of electrical energy after each heat-and-cool cycle. To put it simply, it theoretically only needs 1,000 such endothermic cycles to produce 0.1 kWh (10 watt-hours) of energy. According to the battery specifications that are common in mobile phones today, this is actually enough to charge about 50% of mainstream models.
However, since the team has not disclosed any more data, it is not known how much temperature difference it takes to complete the so-called "endothermic cycle", and how long the reaction time will take. At the same time, the associated cost of thermoelectrochemical materials is largely unknown (because if it were really cheap, it's hard to imagine that the report wouldn't make a big deal out of its cheapness).
Of course, in any case, it is compared to the ultra-miniature heat pump, which is basically only theoretically possible, and basically cannot be manufactured. Thermoelectrochemical cell technology does open the door to possibilities for the use of waste heat from chips in small mobile devices.
Theoretically, it can replace a coin cell battery, but the cost may be the biggest problem
Because of this, there is an argument that this new technology may help to eliminate the current more polluting button batteries. Of course, in principle, coin-cell-powered devices are inherently low-energy, and having a thermoelectrochemical cell absorb ambient heat to power it is a very environmentally friendly move.
But considering that button batteries, as well as devices powered by button batteries (usually various small sensors and timing devices), are mostly very cheap, we think that thermoelectrochemical batteries may not necessarily "benefit" them so quickly.
Thermoelectrochemical batteries have always been very promising in the field of medical devices and professional sports equipment, which indirectly explains its cost
In contrast, professional sports watches and wearable sensors, which also do not consume much more power, but have a high product premium, seem to be more likely to be the first products to be benefited by thermoelectrochemical batteries. After all, looking at this market, it is not difficult to find that many of them already use high-cost energy conversion devices such as solar cells. If you add thermoelectrochemical batteries, there is a high probability that they can withstand it, and maybe it will be more popular with specific user groups.
As for when it will be popularized in mobile phones, tablets, or more types of consumer electronics, it depends on the needs of users at that time.
[The picture in this article comes from the Internet]