I test a lot of 18v drills from Milwaukee, DeWalt, Bosch, Makita, and Hitachi and the ones with the most torque and longest battery life are the 3-speed range ones from DeWalt. No need for the heavier hammer drill versions as you will not use this function. Second best are the drills from Milwaukee and in my testing Makita is in the bottom tier along with Ryobi and Rigid. All but DeWalt and Rigid only make 2-speed range drills which greatly limit their performance.
Most of the cordless drills are provided with smaller and lighter battery packs so that the drill feels lighter in a consumer's hand when they pick it up at a store. The DeWalts have the largest battery packs and their lithium-ion XRP ones have a 2-year replacement warranty which is the best available.
A drill I have not tried but might work is the 4-speed range Rigid drills. They have a low range speed of 0-450 like the DeWalt. I use the DeWalt battery packs on the cordles drills I am testing and also for personal use on a 18v cut-off saw, a 18v 5-1/2" circular saw, and a 18v mini shop vac. It is great to be able to buy the tool only for under $100 and use the battery packs and chargers I already have in the shop.
The batteries are designed to provide a steady flow of current and will recover after a few minutes to provide additional current if needed. It is important to recharge the battery immediately after using it for extended periods and not store it away partially drained. You will get a lot longer life from the batteries if you do this.