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Thread ID: 149572 2021-02-06 20:27:00 How Long Will EV charging Remain At A Low Price? zqwerty (97) PC World Chat
Post ID Timestamp Content User
1474941 2021-02-13 07:13:00 Some manufacturers make batteries that can last the life of the car, this tech already exists.

And the lifetime of the car is how long? :confused:

I love this "Lifetime Guarantee" thing that the Spin Doctors put out years ago.

Whose lifetime, yours, mine, your cats?????????????

Absolute advertising crap that is unenforceable :lol:.

I read the other day that the Greens are going to store main line electricity. There wasn't any detail but I wish them luck. :lol:
B.M. (505)
1474942 2021-02-13 08:06:00 Teslas current batteries are good for 500,00km and they are working to double double that. Not many cars last longer than that.
And even the first gen batteries were pretty good, see this one futurism.com not marketing, real world 900,000 km and on it's second battery.
Here's another electrek.co

Yes there's marketing involved, EV manufacturers know people are wary of battery life and they need to have products that last a reasonable amount of time in order to be able to sell their cars.
dugimodo (138)
1474943 2021-02-13 20:30:00 Teslas current batteries are good for 500,00km and they are working to double double that. Not many cars last longer than that.
And even the first gen batteries were pretty good, see this one futurism.com not marketing, real world 900,000 km and on it's second battery.
Here's another electrek.co

Yes there's marketing involved, EV manufacturers know people are wary of battery life and they need to have products that last a reasonable amount of time in order to be able to sell their cars.

All very well having batteries that can do 500000 Km but most vehicles when they reach about 200000Km start developing suspension, drivetrain and other aging issues. What sort of issues will the EVs have at about 200 to 300000Km??
paulw (1826)
1474944 2021-02-13 21:49:00 EV's don't have a drive train, the speed is controlled electronically through the motors on the wheels. Lack of mechanical bits and pieces is one of the attractive features of electric vehicles, also good to spectacular acceleration.

500,000 km battery packs I'll believe when I see them, think about the best lithium battery pack you have ever had in your laptop, a use where lifetime and capacity is important, and surely the manufacturers have done their best in these areas with the better brand laptops etc. Mine have gone down to half capacity in about three years of not very arduous use, the cars will be much more demanding of the battery packs in the vehicles.
zqwerty (97)
1474945 2021-02-13 23:57:00 From dugimodo’s link:

10796

So I’m expected to believe that if after 7 years the battery drops to 65% of its as new capacity, Tesla will replace and install a new battery completely free of charge.

Yeah right, Of course I believe them. :rolleyes:
B.M. (505)
1474946 2021-02-15 03:18:00 EV's don't have a drive train, the speed is controlled electronically through the motors on the wheels.

Actually, many EVs still have a drivetrain comprising a single speed gearbox, differential and half shafts, so likely also some universal joints in there too.
The advantage of motors on the wheels is the absence of drivetrain hardware, but it is countered by a weightier wheel as 'unsprung mass' which is detrimental to handling and ride comfort, and economy.


500,000 km battery packs I'll believe when I see them, think about the best lithium battery pack you have ever had in your laptop, a use where lifetime and capacity is important....

Yeah, the manufacturer with the best battery will be the longterm winner. There is a major difference between a car (with very expensive battery) vs a laptop battery.
Users can typically tolerate the cost of a new laptop battery or an entirely new laptop, but drivers are unlikely to be as tolerant with the option of replacing car batteries or entire cars when the batteries age. These must have reliable cells. Any manufacturer shipping a car with a crap cell will fairly quickly get a very bad reputation, or get killed on warranty costs.
Paul.Cov (425)
1474947 2021-02-15 03:23:00 So I’m expected to believe that if after 7 years the battery drops to 65% of its as new capacity, Tesla will replace and install a new battery completely free of charge.

Yeah right, Of course I believe them. :rolleyes:

Any decent EV has strong thermal management of the battery pack, plus a dedicated Battery Management System, which manages temperature, charge rate, and the overall levels of charge/discharge allowed (ie they don't let you drive the battery to zero, or charge to 100%). Info so far suggests that charging to 100% will degrade traditional lithium ion cells, and is one of the reasons the battery management system will slow the rate of charge when the battery is at either the very low or very high states of charge.

EVs with passivley cooled battery packs should be totally avoided (based on tech to date).
Paul.Cov (425)
1474948 2021-02-15 07:53:00 Battery packs are inherently nasty and kludgy, I have done quite a bit of work and research on NiCad packs in another life and the biggest problem is that a battery is composed of stacks of cells arranged in series electrically.

Even starting with identical cells, (yeah right) the cells quickly age differently and a weak cell will be soon stressed by the stronger ones to the point that the weakest cell determines the performance of the entire battery pack.

I won't go into the charge and discharge characteristics in detail but suffice to say each individual cell cannot be monitored to ensure the battery is at peak condition, in a 48 Volt battery there will be approx 15 to 18 cells in series not all in the same position in the pack and therefore each cell is subjected to different temperatures in the pack over time resulting in degradation of each cell in a different way.
The temperature of a cell determines it's optimal charge voltage. Negative temperature co-efficient of a few millivolts per degree centigrade.

Engineers are used to working with closely specified devices within close tolerances and they tend to treat batteries the same way as resistors, capacitors etc in their designs. This is a big mistake as batteries are a completely different animal, so to speak, and have quite wide performance tolerances and aging characteristics.

In a word, "horrible".
zqwerty (97)
1474949 2021-02-15 22:33:00 Any decent EV has strong thermal management of the battery pack, plus a dedicated Battery Management System, which manages temperature, charge rate, and the overall levels of charge/discharge allowed (ie they don't let you drive the battery to zero, or charge to 100%). Info so far suggests that charging to 100% will degrade traditional lithium ion cells, and is one of the reasons the battery management system will slow the rate of charge when the battery is at either the very low or very high states of charge.

EVs with passivley cooled battery packs should be totally avoided (based on tech to date).

I agree, the Battery Management System is quite sophisticated and covers quite a few possibilities, but the problem for me is the battery itself.

I can’t get my head around placing 110 cells in series to make up 400v and not one cell failing in 7 or 8 years. The old adage that “A chain is only as strong as its weakest link” comes into play here.

Ok, we parallel another similar battery but we are now in a position of in the case of say a short circuit we now have two batteries supplying the amps and on it goes.

But, as I’ve said before, my biggest fear is one of these vehicles being involved in a “pile-up” and just exploding.

Anyway, for those interested in the subject but aren’t up with the terminology HERE (www.automobilemag.com) is a good link.
B.M. (505)
1474950 2021-02-16 06:36:00 I recall hearing that a fuel tank is many times more likely to explode on you than a battery, and we've all been happily driving potential bombs around for a long time so why worry about a new one :)

here's someone's take on it money.cnn.com
dugimodo (138)
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