"Why is my battery life less than expected?"に関する回答Hi Kevin, It's possible that either your battery is dead or your laptop charger does not function properly. As batteries age, the repeated charging and depletion naturally lessens the battery's ability to hold a charge. If you need to learn how to replace the battery, you can do so with the guide Lenovo Yoga 3 14 Battery Replacement. If your battery is not dead or dying, you may need to replace your laptop charger. It may no longer function due to natural wear and tear.
"Why is my laptop overheating"に関する回答Kevin, Your laptop's fan may not be working properly and may be in need of cleaning and/or replacement depending on the problem. Your laptop may also be bogged down with useless programs. Try checking out the troubleshooting page here. Lenovo Yoga 3 14 Troubleshooting