The bad battery blade(s) can be easily identified by running a full battery test or life expectancy test.
Repair shops have a starting rate of $500 USD minimum for this service and parts. Alternatively, you could DIY and save the money towards your next car, Please read the following notes and precautions before moving forward:
1. First and foremost, you should have basic electrical knowledge, Without some base electronic experience or knowledge, by touching the + and - on a high voltage battery pack could result in injures and may even cause death.
2. You should disconnect the orange servicei plug before moving forward with the repair. This will reduce the battery voltage from 200v into the 100v range.
3. You should only repair the battery pack with used blades in similar capacity. Be sure to use battery replacement blades closest in mAh. You cannot use a 3000mAh battery with a 6500mah battery. Doing so may result in error code(s).
4. Reserve a good half day to perform the repair, take your time and do it right. (just FYI a professional can repair a Gen 2 pack in 60 min, 90 min on Gen3 pack.)
5. If you have any questions or concerns, PriusChat.com is the best place to look for answers and to post your questions. There are also many YouTube video available to guide you through the process.
6. Once the repair has been completed, drive the car gracefully for the first couple of days and let the NiMH battery blades balance themselves with this break in period.

P0A80 is a warning code informing you the performance of the battery pack is bad. At this time the life expectancy test should result in less than 50% remaining in total capacity.
Toyota dealer or most repair shops offer you only one solution for this type of situation. A complete pack replacement that usually will result with an overall cost that is higher than the value of your vehicle.
Fortunately you could refresh/revive the battery pack with the Prolong charger and discharger, the whole refresh process takes about 3 days. Each refresh last 6~12 months, the more you drive, the less frequent you will need to refresh the battery.

Green Bean Battery company was built around the core of creating a reliable reconditioned hybrid battery and extending the hybrid battery life, they have grown to create a proprietary hybrid battery reconditioning process that enable them to offer a Lifetime Warranty and go above and beyond with their customer service.

After 6 years of research, development and testing, Dr. Prius proudly presents you the Sodium-ion Battery Upgrade solution that take your hybrid vehicle to the next level.
Dr. Prius NexPower Sodium-ion Upgrade Pack directly replaces your old NiMH pack and brings you the following benefits:
1. 1/2 of the weight of the original battery pack Stock NiMH battery weights 80 lbs! Dr. Prius sodium-ion pack weight less than 40 lbs.
2. 4 times more powerful Dr. Prius NexPower Sodium-ion pack delivers 400Amp peak power compared to 100Amp peak power from stock NiMH battery.
3. Better fuel economy with improved EV range NexPower Sodium-ion pack maintain an optimal voltage to trick the computer in favor of electric power. Resulting in better fuel economy
4. Highest Level of safety NexPower Sodium-ion solution is proven to be safe and has been tested in extreme conditions around the world (sub-zero temperature, extreme humidity, extreme desert heat) with more than half million miles logged, test videos available on YouTube, keyword "Dr. Prius lithium test"
5. Toxic free No more hazardous chemical emitted from NiMH chemistry.
5. Affordability NexPower Sodium-ion Upgrade Battery replacement costs less than recondition pack! sodium is abundant and we translate the saving onto customers.