Is Fast Charging Bad For Battery Life? -- Engineering Explained Answers the Question

• ? Fast Charging Accelerates Battery Degradation
  Studies show that higher charging rates lead to faster battery wear, with faster degradation occurring when using fast charging frequently.
• ? Why Faster Charging Degrades Batteries
  Fast charging throws lithium ions into the battery faster than they can properly diffuse within the graphite particles, causing lithium plating and eventual damage.
• Factors Influencing Degradation
  Three main factors affect degradation: state of charge, charge rate, and battery temperature. At high states of charge, the lithium ions have fewer available spaces, increasing the risk of lithium plating.
• ? Temperature’s Role
  Warmer batteries reduce the risk of lithium plating, but temperatures that are too high can increase SEI layer formation, causing long-term capacity loss.
• ? Practical Solutions
  Electric vehicles automatically adjust charging rates and temperatures to minimize the effects of fast charging. While fast charging has some impact, modern batteries and vehicle systems mitigate most negative effects.

• 5% degradation difference: A study found that after 50,000 miles, a car charged exclusively with fast chargers retained 70% of its original capacity compared to 75% for slow-charged cars.
• Temperature effect on degradation: A warmer battery charged at around 25°C could achieve over 3,000 full cycles before significant capacity loss occurred, compared to cold batteries, which suffer more from lithium plating.

JayGT4 said:

Here's a text summary (by ChatGPT)

• ? Fast Charging Accelerates Battery Degradation
  Studies show that higher charging rates lead to faster battery wear, with faster degradation occurring when using fast charging frequently.
• ? Why Faster Charging Degrades Batteries
  Fast charging throws lithium ions into the battery faster than they can properly diffuse within the graphite particles, causing lithium plating and eventual damage.
• Factors Influencing Degradation
  Three main factors affect degradation: state of charge, charge rate, and battery temperature. At high states of charge, the lithium ions have fewer available spaces, increasing the risk of lithium plating.
• ? Temperature’s Role
  Warmer batteries reduce the risk of lithium plating, but temperatures that are too high can increase SEI layer formation, causing long-term capacity loss.
• ? Practical Solutions
  Electric vehicles automatically adjust charging rates and temperatures to minimize the effects of fast charging. While fast charging has some impact, modern batteries and vehicle systems mitigate most negative effects.

Insights Based on Numbers

• 5% degradation difference: A study found that after 50,000 miles, a car charged exclusively with fast chargers retained 70% of its original capacity compared to 75% for slow-charged cars.
• Temperature effect on degradation: A warmer battery charged at around 25°C could achieve over 3,000 full cycles before significant capacity loss occurred, compared to cold batteries, which suffer more from lithium plating.

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slothinker said:

> 5% degradation difference: A study found that after 50,000 miles, a car charged exclusively with fast chargers retained 70% of its original capacity compared to 75% for slow-charged cars.

It would be interesting to know if the cars tested were charged to 100% or, if not, to what level and was that level used consistently?

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Scandinavian said:

Perhaps, but the data seemed to come from a Nissan Leaf! In a hot climate! That is an air cooled battery which quite frankly is of no use whatsoever compared to a long distance cruiser like the Taycan. More likely to compare it to a Tesla of any model!

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slothinker said:

So as to the Taycan, there are no studies or prognostications comparing charging to 85% via, say, ElectrifyAmerica with charging to 85% at home using 220V charger over a period of years?

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Fun TC Driving said:

Was the Taycan’s battery chemistry changed in the 2025 models?

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Jonathan S. said:

"A study found that after 50,000 miles, a car charged exclusively with fast chargers retained 70% of its original capacity compared to 75% for slow-charged cars."
That can't be right -- even such a best-case 25% degradation after merely 50k miles does not match up with either anecdotal accounts or quantitative studies.

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Jonathan S. said:

"A study found that after 50,000 miles, a car charged exclusively with fast chargers retained 70% of its original capacity compared to 75% for slow-charged cars."
That can't be right -- even such a best-case 25% degradation after merely 50k miles does not match up with either anecdotal accounts or quantitative studies.

Click to expand...