Electric motor to swap for SBC

[RecklessWOT]

That's just not true.

The reason it only fast charges to 80% is that there is a safe charging curve for batteries. The last 20% of the charge is what takes the longest to charge without damaging the battery. All of these cars have their own built in charging regulation systems that are designed to not allow the batteries to be damaged during charging. There is a possibility to damage some lithium batteries in other applications when fast charging due to using chargers not specifically designed for that battery, heat created during fast charging, or continuing to charge once the battery is full. The automotive systems don't have any of these problems as most of them carry the charging safety systems on-board and have battery cooling systems in place. That's why when you walk past an electric car charging at a station, you can often hear a fan going as it is dumping waste heat from the charge.

The biggest issue with fast charging is that your charging for minimum time, not maximum efficiency, so you waste more energy charging the battery than you would normally. A good analogy would be trying to get somewhere fast, so you are getting worse gas mileage. Although in this case the loss in efficiency is much less than in the gas engine analogy.

So it is mostly true. They may only charge 80% to avoid damaging the battery, but the reason behind that is because fast charging can in fact be very bad for batteries, the whole reason they stop at 80% even according to you. So to say "that's just not true" is actually a blatant lie. It is in fact very true if what you say is really how it works, but they've found a way to minimize the risk. I'm sure even stopping at 80% isn't terrific for your battery, just not as bad as it could be. And even then, is only ever charging your battery to 80% every time really that good for it? I feel like you'd need to charge it up to 100% most of the time, but in real world usage that's probably almost never the case.

 

[Bextreme04]

So it is mostly true. They may only charge 80% to avoid damaging the battery, but the reason behind that is because fast charging can in fact be very bad for batteries, the whole reason they stop at 80% even according to you. So to say "that's just not true" is actually a blatant lie. It is in fact very true if what you say is really how it works, but they've found a way to minimize the risk. I'm sure even stopping at 80% isn't terrific for your battery, just not as bad as it could be. And even then, is only ever charging your battery to 80% every time really that good for it? I feel like you'd need to charge it up to 100% most of the time, but in real world usage that's probably almost never the case.

No... forcing a battery to charge outside of it's optimal range can be bad for it, but isn't automatically bad for it. They don't STOP charging it at 80%, they just start charging it at a slower rate. The fast charge takes it to 80% in 15 minutes, but then can take another 30 minutes or more to charge the remaining 20%. Saying that fast charging a battery will destroy it is not true as a general rule.

Its like saying "reving your engine to the redline will destroy it". Running it at redline for an extended amount of time will definitely hurt the engine, but it is specifically designed to run up to redline before you shift and if used properly wont damage the engine at all.

There is an acceptable range to charge a battery, depending on the battery design and chemistry. The region of the battery capacity that generally takes a charge the fastest is from about 20%-80% capacity. If you try to force a battery to take a charge quickly outside of that region, there can be other consequences that may or may not damage the battery. The most efficient, and best, region for battery longevity and for the battery charge to be at is that same 20-80% range. Leaving one of these lithium batteries at a charge either higher or lower than that range can severely negatively affect their life or damage the batteries. Charging up to 100% and then immediately driving it until it gets down to 20% and then charging again isn't bad for the batteries, but it is a huge waste of time. You take twice the time to get 1/3 the charge.
You save a lot more time by only charging up to the top of that high-efficiency region and then driving to the bottom of that region before doing it all over again and it doesn't hurt the batteries.

 

[RecklessWOT]

No... forcing a battery to charge outside of it's optimal range can be bad for it, but isn't automatically bad for it. They don't STOP charging it at 80%, they just start charging it at a slower rate. The fast charge takes it to 80% in 15 minutes, but then can take another 30 minutes or more to charge the remaining 20%. Saying that fast charging a battery will destroy it is not true as a general rule.

Its like saying "reving your engine to the redline will destroy it". Running it at redline for an extended amount of time will definitely hurt the engine, but it is specifically designed to run up to redline before you shift and if used properly wont damage the engine at all.

I understand what you're saying but it's not so black and white like you're making it out to seem, it still can't be great for the battery. Especially your analogy about redlining your engine. Of course if you hold it at redline for a long time it will blow up, but saying bringing your car up to redline before you shift won't damage the engine at all isn't true either. Yes it is designed to do so, but it still isn't the ideal condition to operate even for short periods of time. If you bring your engine close to redline before you shift every time you will NOT get the same life out of that engine as if you only did that once in a blue moon. It won't just grenade, but it does wear the moving parts at a faster rate, and all the extra vibrations are bad for seals, etc. There's really no part of a street car that likes running at redline besides the guy behind the wheel. That's why old folks' cars last so much longer than a teenager's.

I'm willing to bet 5 years from now a car battery that gets fast charged every day will not be in the same condition as a battery that slow charged overnight every time.