I’ve owned an EV for a while now, and one thing I’ve paid attention to is how my charging habits affect the battery over time. For a long time, I would usually charge it to around 90–95% each time. It felt like a good middle ground, I had enough range for daily driving without going all the way to 100%. After some months, though, I started wondering if there was still room to improve battery longevity without making things too inconvenient.
From what I’ve learned, EV batteries generally handle being kept at very high charge levels (like 95% or 98%) less well over long periods. The closer the battery stays to full, the more stress it experiences, especially if it sits at that level for many hours. Heat also plays a big role, charging in hot conditions or letting the battery get warm while at a high state of charge can speed up degradation.
To understand my own patterns better, I started tracking my charging sessions more closely. I looked at how often I was charging to 90% or above, what time of day I usually charged, and how the battery temperature behaved. This helped me notice that I was often charging during warmer parts of the day without really thinking about it.
After seeing the data, I made some small adjustments. Instead of charging to 90–95%, I started setting the charge limit to around 80–85% for regular daily use. I only raise it higher when I know I’ll need more range the next day. I also try to avoid charging during the hottest hours when possible. These changes weren’t dramatic, but they felt like a reasonable balance between convenience and taking better care of the battery.
Here’s a simple example of the kind of logic I use in a small script to analyze my charging data:
import pandas as pd
df = pd.read_csv("charging_logs.csv")
# Check how often I charged above 90%
high_charges = df[df['soc_end'] >= 90].shape[0]
total_charges = df.shape[0]
print(f"Charged above 90% in {high_charges} out of {total_charges} sessions")
This kind of tracking doesn’t need to be complicated. Even basic analysis can show whether I’m regularly charging to high levels without really needing to.
What I’ve found now is that I don’t have to be extremely strict with every charge. Small, consistent habits, like lowering my daily charge limit a bit and being more mindful of temperature, seem to matter more than trying to optimize every single session perfectly. For me, moving from charging to 90–95% down to 80–85% for normal use has been a practical middle ground.