Tang Yue lugged the solar panels onto the Mars Wanderer's trailer. The RTG and backup batteries were also placed on the vehicle. Tomcat was about to set off on a long-distance trip. The latter didn't need any food or supplies, but power was necessary. He had given all the batteries and solar panels that the trailer could take to Tomcat.
It could be foreseen that when Comet Tomcat-Tang-Mai I hit Mars, it would trigger an extremely serious cataclysm. Tomcat might survive the shockwave and subsequent quakes, but the large amount of matter that would be tossed up into the sky from the impact would plunge Mars into endless darkness. The dust that blotted out the sky would cut off any solar power. This was the main problem that Tomcat faced.
Therefore, Tang Yue had installed the batteries on the vehicle, afraid that Tomcat would suffer from a lack of power.
