I am going on a school trip to Costa Rica for a bit over a week and I was going to make and bring a Solar Powered phone/USB charger for my phone and camera.
The Solar Powered charger will have 2 internal Li-Ion batteries which are 3.7VDC and 2800 mAh each. For a total of 7.4VDC and 2800 mAh in total.
Are there any restrictions or laws that would prevent me from bringing homemade electronics or these Li-Ion batteries on a plane from Canada to Costa Rica?