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BU-808: How to Prolong Lithium-based Batteries (2023)

batteryuniversity.com

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Re: BU-808: How to Prolong Lithium-based Batteries (2023)

#31

Post by stavros »

VorpalWay wrote: post #23
stavros wrote: post #8

Earlier quoted context omitted.

I don't think this advice is useful. You're going to use your devices, so you won't control the temperature or, largely, the charge percentage. I think good advice is to keep your devices as cool as you can (ie don't leave your cars in sunlight when there's shade), which you probably did anyway, and keep the battery between 20% and 80% as much as possible. If the battery is going to stay unused for a while, leave it…

> I think good advice is to keep your devices as cool as you can (ie don't leave your cars in sunlight when there's shade), In some climates, such as where I live, the larger issue is the cold in the winter. From what I understand, Li-ion batteries don't like being charged below 0 C. And it is not uncommon for it to dip to -15 C or even -20 C here. Really, from what I understand, batteries want to be kept above freez…

Yeah, they lose capacity temporarily when it's very cold. Most EVs now precondition the battery before charging by heating it up.

Re: BU-808: How to Prolong Lithium-based Batteries (2023)

#32

Post by SV_BubbleTime »

kuerbel wrote: post #30
SV_BubbleTime wrote: post #11

Earlier quoted context omitted.

> Do EV manufacturers use any other tricks not covered by this? Automotive EE here. EV aren’t ready for world wide use. That statement is constantly ignored by people in California who see zero issues with their new expensive fancy cars. Shortest version… The heating and cooling systems of the battery are there to prevent damage. BUT… who powers the heating and cooling systems? The battery of course. In a traditional…

...what? You leave your car plugged in, and that's it. Then the BMS will take care of the battery without having to use it's energy. If I preheat the car it also preheats the battery. If it's not warm enough it won't allow full recuperation. Oh my god, I have to use THE BRAKES for a few minutes, literal trash car. And all those people in Norway, you know, with their heat pumps and EVs. Obviously life just grinds to a…

Cool. And when you need to drive it? Most systems do not keep the battery heater running indefinitely.

No one is talking about the brakes.

I’m an automotive engineer that has worked for two of the big4. What is your experience?

Re: BU-808: How to Prolong Lithium-based Batteries (2023)

#33

Post by SV_BubbleTime »

pengaru wrote: post #26
SV_BubbleTime wrote: post #11

Earlier quoted context omitted.

> Do EV manufacturers use any other tricks not covered by this? Automotive EE here. EV aren’t ready for world wide use. That statement is constantly ignored by people in California who see zero issues with their new expensive fancy cars. Shortest version… The heating and cooling systems of the battery are there to prevent damage. BUT… who powers the heating and cooling systems? The battery of course. In a traditional…

How is this not an instance of "perfect is the enemy of good enough?"?

Depends.

I have a vehicle in my personal shop right now. It needs a new battery, it is effectively totaled.

The battery costs more than the vehicle.

The effort for me to replace the battery modules (not even the cells inside of them) involves taking the entire suspension out, and then, you have the ACTUALLY FATAL issue of working on the battery pack. You need 1000V+ gloves that expire every six months, composite ratchets and sockets, and for me high voltage certification.

There is nothing on an ICE vehicle that can kill you while working on its parts.

I will be downvoted by people who need (literally) to defend their purchase. Always am on this topic.

Re: BU-808: How to Prolong Lithium-based Batteries (2023)

#34

Post by ninalanyon »

SV_BubbleTime wrote: post #11
user_7832 wrote: post #6

+1 for battery university, they're an excellent source. Does anyone have any other suggestions for similarly technically deep (while approachable) articles on any other facet consumer electronics? My understanding from this article is that: 1. Charge the battery to as low a max percentage as possible (till about 65%) 2. Keep it as cool as possible (up to zero degrees C at least) 3. Use it as little as possible before…

> Do EV manufacturers use any other tricks not covered by this? Automotive EE here. EV aren’t ready for world wide use. That statement is constantly ignored by people in California who see zero issues with their new expensive fancy cars. Shortest version… The heating and cooling systems of the battery are there to prevent damage. BUT… who powers the heating and cooling systems? The battery of course. In a traditional…

They seem to be working just fine here in snowy Norway.

Re: BU-808: How to Prolong Lithium-based Batteries (2023)

#35

Post by kuerbel »

SV_BubbleTime wrote: post #32
kuerbel wrote: post #30

Earlier quoted context omitted.

...what? You leave your car plugged in, and that's it. Then the BMS will take care of the battery without having to use it's energy. If I preheat the car it also preheats the battery. If it's not warm enough it won't allow full recuperation. Oh my god, I have to use THE BRAKES for a few minutes, literal trash car. And all those people in Norway, you know, with their heat pumps and EVs. Obviously life just grinds to a…

Cool. And when you need to drive it? Most systems do not keep the battery heater running indefinitely. No one is talking about the brakes. I’m an automotive engineer that has worked for two of the big4. What is your experience?

driving an ev for the past 2.5 years with 97% SOH remaining. So I must be doing something right wrt treating the battery nicely. And I don't have a garage, it's outside most of the time. I drove thousands of km in subzero C temperature.

>Cool. And when you need to drive it? Most systems do not keep the battery heater running indefinitely.

I get in and put it into drive. When it's cold, I preheat it, I can program departure times, so the battery is conditioned and the cabin warmed in advance. Even at sub-zero temperatures, it always starts reliably, unlike a diesel engine, which, as you know, requires preheating and can struggle with extreme cold starts. Also requires winter diesel.

Re: BU-808: How to Prolong Lithium-based Batteries (2023)

#36

Post by ninalanyon »

SV_BubbleTime wrote: post #32
kuerbel wrote: post #30

Earlier quoted context omitted.

...what? You leave your car plugged in, and that's it. Then the BMS will take care of the battery without having to use it's energy. If I preheat the car it also preheats the battery. If it's not warm enough it won't allow full recuperation. Oh my god, I have to use THE BRAKES for a few minutes, literal trash car. And all those people in Norway, you know, with their heat pumps and EVs. Obviously life just grinds to a…

Cool. And when you need to drive it? Most systems do not keep the battery heater running indefinitely. No one is talking about the brakes. I’m an automotive engineer that has worked for two of the big4. What is your experience?

> And when you need to drive it?

When I need to drive me EV I open the door, get in, close the door, put it in drive and drive off.

Were you expecting something different? I'm in Norway by the way where it is expected to be -15 C in a few days; after eight years of EV driving (2015 Tesla S 70D) I am not anticipating any problems.

> What is your experience?

I've told you mine, what's yours? Or will you argue from authority again?

Re: BU-808: How to Prolong Lithium-based Batteries (2023)

#37

Post by avidiax »

I may be a bit odd, but I store lithium ion battery containing electronics in the vegetable drawer in the fridge. You lose 20% of capacity in a year if you have 100% state of charge but only 6% loss of capacity at refrigerator temperatures. So tool batteries, small electronics and whatever else that isn't used weekly gets put in.

I also try to charge fully only just before use (and only if I need 100%), and store at partial charge. If I am charging for storage, I just set a 30 minute timer. Since 1C charging is the most common, 30 minutes at 1C will be about 50% state of charge from empty, which is useful for items with no state of charge indicator.

I use AlDente[1] on my Apple laptops, and the 80% charge feature on my Pixel phone. My bedside phone charger is a slow charger.

Maybe I'm doing too much to manage my batteries, but I also haven't needed to retire anything for having a bad battery in many years, nor had items with dwindling capacity.

[1] https://github.com/AppHouseKitchen/AlDente-Battery_Care_and_...

Re: BU-808: How to Prolong Lithium-based Batteries (2023)

#38

Post by s-y »

SV_BubbleTime wrote: post #11
user_7832 wrote: post #6

+1 for battery university, they're an excellent source. Does anyone have any other suggestions for similarly technically deep (while approachable) articles on any other facet consumer electronics? My understanding from this article is that: 1. Charge the battery to as low a max percentage as possible (till about 65%) 2. Keep it as cool as possible (up to zero degrees C at least) 3. Use it as little as possible before…

> Do EV manufacturers use any other tricks not covered by this? Automotive EE here. EV aren’t ready for world wide use. That statement is constantly ignored by people in California who see zero issues with their new expensive fancy cars. Shortest version… The heating and cooling systems of the battery are there to prevent damage. BUT… who powers the heating and cooling systems? The battery of course. In a traditional…

Are you a technician or an engineer? And as a follow up, what part of the vehicle do you engineer?

Because this sounds a lot like a case of a dentist seeing a lot of cavities and making conclusions that teeth are "bad tech".

I live in a climate that's in yearly flux from -20 to +35 C and EVs have been normal here for a long time(7+ years) with no major issues. What parameters and therefore regions does your statement cover? I'm sure you can't run an EV in Syberia(RU), but people with petrol cars there have to run them even parked to avoid freezing during the winter so there will always be extremes.

As for the commercial equation: BYD and Tesla don't seem to be fitting that narrative. So this is not a matter of a marketing mistake - but an overall execution on the failed manufacturers.

Re: BU-808: How to Prolong Lithium-based Batteries (2023)

#39

Post by jwiz »

simulator5g wrote: post #22
stavros wrote: post #9

Earlier quoted context omitted.

Those really make my phone overheat, so I avoid them. Didn't they heat yours up?

They’re a joke, I used to have one in my car and the combination of sunlight & internally produced heat would make my phone shut off & display a “iPhone is too hot” message. Even when it’s cold outside.

I think that's just sun+charging, not wireless charging specific.

Re: BU-808: How to Prolong Lithium-based Batteries (2023)

#40

Post by gruez »

avidiax wrote: post #37

I may be a bit odd, but I store lithium ion battery containing electronics in the vegetable drawer in the fridge. You lose 20% of capacity in a year if you have 100% state of charge but only 6% loss of capacity at refrigerator temperatures. So tool batteries, small electronics and whatever else that isn't used weekly gets put in. I also try to charge fully only just before use (and only if I need 100%), and store at…

>You lose 20% of capacity in a year if you have 100% state of charge but only 6% loss of capacity at refrigerator temperatures.

Source? The common figure for smartphone batteries is "at least 80% capacity after 2 years", and that presumably includes cycles, not just leaving it charged.

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