It will not harm the battery because the Tesla Model Y is charged with lithium-ion batteries, and lithium-ion batteries have good charging and discharging characteristics, will not cause greater damage due to overcharge or overdischarge, and Tesla's car charging system is also very intelligent, can automatically judge the state of the battery and control the charging current. In addition, Tesla's batteries also have a very good feature, reversible charging, that is, they can prevent damage or overload through fuses or circuit breakers, further protecting the battery. Therefore, the Tesla Model Y onboard charge will not harm the battery, and can also ensure the safety and life of the battery.