@Lizzylee2000: As our range of tablets are all closed units, it won't be possible for you to fit a new battery yourself, as this would need to be done by an authorised Samsung engineer at a repair location near you.
Are you able to confirm the model name/number of the affected tablets? Also, are you using the USB cable that came packaged with the devices, along with an official Samsung plug adapter? When you connect the tablets to the charger, does an indicator appear on screen to show that it is charging, and the estimated time for the charge to reach 100%? If you have access to a home computer, have you tried connecting via USB to see if you notice an improvement?
