Concealed laptops stolen from cars. Lithium batteries identification gadget is the cause is theory. True ?

In my city a lot of laptops are stolen from cars even though these laptops have been concealed under seats, shopping items. Totally invisible - but thievies are able to identify cars with these lap tops. And they are stolen. The theory making its way around the city is that thievies have a sensor gadget that that identify lithium ion batteries and as a result can pinpoint devices that uses these batteries be it phones or laptops. I'm no technical person. But is there such a thing in this world. If so what can be done to blunt this ? Thanks.