Active cooling in lithium (or any chemistry) batteries exists to allow fast charging and discharging of the battery, as those actions produce heat. Without any cooling system, you're limited by the passive heat dissipation of the battery, which largely depends on the internal resistance. You can lower the internal resistance at the expensive of some other properties (mostly efficiency).

If you don't believe this is a problem in any battery chemistry, I challenge you to find a battery that does not heat up while being charged (they all do, due to thermodynamic inefficiencies). Thermal runaway in Lithium-ion specifically is largely an effect of the lithium decomposing as a result of large heat input (by a short or physical damage). Once this has occured the battery will go through several stages of burning.