There are things you can do to prolong your power bank’s lifespan, while also ensuring you can use it safely. Larger and more expensive power banks with greater capacities — like a 20,000mAh model instead of a smaller 5,000mAh one — also generally last longer, according to Anker. It’s also important to stop using a power bank and dispose of it properly if it’s been pierced or damaged, which includes accidental drops. If it’s taking significantly longer to fully recharge the power bank than when it was new or if the number of times you can use the power bank to recharge your device has been reduced, it might be time to replace it. Power banks, particularly smaller models, will always get warm when being charged or while powering other devices.