in General the Prius battery wear out over time, but several conditions effect when that happens. the Prius battery chemistry the number of charge and discharge cycles, temperature humidity. You’ll notice two things when it’s time for a new Prius battery pack when Prius battery efficiency is low the Prius engine will run almost all the time under light load, and your fuel economy will drop off significantly.
The first sign that the Toyota Prius battery pack is starting to weaken is when the fuel economy deteriorates. As the electric motor’s contribution Toyota Prius hybrid battery to power at speeds above E.V mode,
The charge level of the the HV prius battery is kept by the control software at a level between 40 percent and 80 percent. on the multi function Prius display of Toyota Prius there is an icon shows level of charge by color and also bar
Green is above normal the computer will limit the charging of the HV battery, also limit the regenerative energy production and even stop completely at maximum permitted level to charge. there will be possible, where as much energy as possible to be extracted from the battery pack serving the actuator
Blue is within the normal all regenerative energy can be dissipated towards the HV battery and battery pack can not and must deliver maximum energy serving.
Pink is below the normal tapping energy from the HV battery to cover the drive become limited and completely stopped at the lowest permitted level. also engine will not turn off, but provide a charging current from the generator to the HV battery pack.
The process will be regulated on the basis of number of parameters, such as generated electric energy MG1, necessary energy saving the HV battery pack (charge level), temperature NIMH-cells and serving the requested electric power drive MG2
Prius repair shop 949 916-0769