I have used a Baseus 30W lighter plug charger and it works fine. I have two types (as well as a 150W AC inverter) and there have been no issues except that you really should only use it when the car is on (engine running) as the alternator voltage is higher than the battery standing voltage.
It charges slowly but it does top up fine. Are you planning to use the laptop while you are driving or in between stops? For me a slow charger is fine but your application might require up to 65W charging if you are needing to charge frequently. Also you might want to try some battery saving methods too so you recharge less often (I know that's obvious) but for reference I can get 8-12 hrs out of a full battery and it might be fruitful for you to check your battery drain situation 🙂
