Review on 🔋 IEIK Smart Charger for Cars, Trucks, Motorcycles, Lawn Mowers, Boats, ATVs - 7-Stage 12V/6A Automotive Battery Charger & 24V/3A Maintainer for Lithium, LiFePO4, Lead-Acid, and Deep Cycle Batteries by Jessie Drury

I have a bank of 3 large batteries (installed in 2015) for a Caterpillar diesel bus. After more than 5 days of inactivity, the engine would not start. After several "repair impulse" cycles on this charger, the batteries start the engine quickly even after 2 weeks of inactivity. The slow heart rate recovery cycle actually lasts 2 days with a large battery pack at 3. The charger can also charge at 5 amps, which is much faster than the heart rate if needed. This charger has definitely extended the life of my batteries. I've been looking for a replacement but now the diesel will start again and hold a charge.