HEAT EXCHANGER

A heat exchanger includes a fluid inlet, a fluid outlet, a first plate, and a second plate. A third plate is disposed between the first plate and the second plate; a first fluid channel is formed between the first plate and the third plate, and a second fluid channel is formed between the second plate and the third plate. The heat exchanger has a first end and a second end; the fluid inlet is close to the first end of the heat exchanger and communicated with the first fluid channel; the fluid outlet is close to the first end of the heat exchanger and communicated with the second fluid channel; and the first fluid channel and the second fluid channel are communicated at the position close to the second end of the heat exchanger.