Sponsored
"Why We're Excited about LFP Batteries for Electric Cars" - Recurrent article
CaliPorsche
Well-Known Member
- First Name
- DAVE
- Joined
- Jul 14, 2023
- Threads
- 17
- Messages
- 239
- Reaction score
- 249
- Location
- California ??
- Vehicles
- 2020 Taycan 4S, 2022 Cayenne S, 964 Widebody Speedster, AMG
So I had never heard much of LFP batteries - then I was at an EA charger last week where unusually (for my experience) there was a chap with a Tesla M3 using an adapter at the charger.
He was at 89% and as he saw I was waiting (behind two others) he came over to me apologetically and said that he had …….. “this piece of shit LFP and the car must be charged up to 100% every single time” ….. it took him no less than 25 minutes after I arrived for him to get there …. Plugged into a 350kw charger.
He was not happy …… “worst buying decision ever”…….
Is this a “feature” of LFP, a Tesla BMS issue or overly malicious compliance.
He was at 89% and as he saw I was waiting (behind two others) he came over to me apologetically and said that he had …….. “this piece of shit LFP and the car must be charged up to 100% every single time” ….. it took him no less than 25 minutes after I arrived for him to get there …. Plugged into a 350kw charger.
He was not happy …… “worst buying decision ever”…….
Is this a “feature” of LFP, a Tesla BMS issue or overly malicious compliance.
Scandinavian
Well-Known Member
- First Name
- Peter
- Joined
- Nov 3, 2019
- Threads
- 52
- Messages
- 3,904
- Reaction score
- 3,549
- Location
- France
- Vehicles
- Taycan T, Aston Martin DB9, Porsche 996 C4 Cab, i4
He had No idea on what he was doing! No reason at all to charge it differently, up to 80% and move on. LFP batteries be charged to 100% without any problems, but there is absolutely no reason to do so.
CaliPorsche
Well-Known Member
- First Name
- DAVE
- Joined
- Jul 14, 2023
- Threads
- 17
- Messages
- 239
- Reaction score
- 249
- Location
- California ??
- Vehicles
- 2020 Taycan 4S, 2022 Cayenne S, 964 Widebody Speedster, AMG
After a quick search seems like over zealous compliance…..
https://www.autoevolution.com/news/...charging-the-lfp-batteries-to-100-187075.html
Dr Bob
Well-Known Member
- First Name
- Andy
- Joined
- Sep 16, 2023
- Threads
- 6
- Messages
- 123
- Reaction score
- 174
- Location
- Falkirk
- Vehicles
- Taycan Turbo
'Must charge LFP to 100% is a load of rubbish'.
What however is just as bad, is that charging to 100% is NOT a good idea. LFP's just like any other Li battery should not be charged to over 100%. If you go past 100% then bad things can happen - like dendrite formation etc - and the chance of that happening is just as bad in an LFP as in an NMC type. Ok the chance of thermal run away is less and the power stored is less but charging over 100% can wreck an LFP. LFPs are inherently safer - but you must not overcharge.
The big issue then is keeping the battery cells in balance so that one individual cell cannot be above its critical voltage whilst the other ones are charging. If it is well out of balance then you can continue to charge a cell when is at 100%.
As an experienced battery chemist, by all means charge to 100% with both LFP and Li Ion but dont do it all the time. Both types of batteries much prefer charging up to the voltage knee (ie 85% ish) and then stopping. I have LFP's on my boat (now installed for 7 years). Their performance (voltage vs SOC is the same today as when I got them 2nd hand from a wrecked EV (Thundersky LFPs) .....but I only ever charge to 85%- after balancing them to 100% on the first day they were installed.
What however is just as bad, is that charging to 100% is NOT a good idea. LFP's just like any other Li battery should not be charged to over 100%. If you go past 100% then bad things can happen - like dendrite formation etc - and the chance of that happening is just as bad in an LFP as in an NMC type. Ok the chance of thermal run away is less and the power stored is less but charging over 100% can wreck an LFP. LFPs are inherently safer - but you must not overcharge.
The big issue then is keeping the battery cells in balance so that one individual cell cannot be above its critical voltage whilst the other ones are charging. If it is well out of balance then you can continue to charge a cell when is at 100%.
As an experienced battery chemist, by all means charge to 100% with both LFP and Li Ion but dont do it all the time. Both types of batteries much prefer charging up to the voltage knee (ie 85% ish) and then stopping. I have LFP's on my boat (now installed for 7 years). Their performance (voltage vs SOC is the same today as when I got them 2nd hand from a wrecked EV (Thundersky LFPs) .....but I only ever charge to 85%- after balancing them to 100% on the first day they were installed.
