Billions of these batteries are in daily use around the world. The vast majority of them do not explode or burst into flames.
Nearly all such incidents have resulted from assembly faults, physical damage to the battery or severe overcharging or short circuiting of the batteries.
As has previously been pointed out, lithium batteries exist with many different chemistries and capacities. Lumping all lithium batteries as extremely dangerous and a hazard to safe flight is foolhardy.
Safer methods (more expensive methods) need to be adopted to keep batteries sufficiently separated and isolated in transport so that if one catches fire, it doesn't affect the others. A single lithium battery fire is spectacular but it usually burns out quickly and self extinguishes. Multiple battery packs are much more dangerous and almost impossible to put out if they catch fire. Isolation and separation would appear to be the key to solving the problem.