The queue ticket said A140. The loudspeaker called number 29.
At three in the morning, a Chengdu driver photographed this slip at a service area. More than a hundred cars were ahead of them. Another account from the same holiday described waiting over five hours just to plug in. They charged for half an hour.
During the National Day holiday, new-energy vehicle traffic on the expressways surged to 17.8 million—nearly twice the usual level. With so many cars in line, everyone had the same goal: get the battery fully charged.
But that’s exactly what you shouldn’t do.
A fully charged car is full at precisely the wrong time when going downhill.
When the motor slows the car, it spins in reverse like a generator, converting kinetic energy into electricity and feeding it back into the battery—but only if the battery has room to take it. Once the charge passes 95%, the battery can accept very little power. The battery management system reduces regenerative braking, or even shuts it off altogether. To prevent overcharging. To keep the voltage from getting too high. To prevent heat buildup. At that point, when you lift off the accelerator, the car coasts farther than usual and slows down sluggishly, while the dashboard displays “Regenerative braking limited.” The brakes have to do the rest.
So not charging all the way isn’t being stingy. It leaves room for regenerative braking to put energy back into the battery.
The manufacturers themselves acknowledge this trade-off. At a launch event in March, BYD set the charging limit at 97%. Wang Chuanfu’s exact words were that the remaining 3% is reserved specifically for recovering energy from braking. From 10% to 97% in nine minutes.
Here’s the interesting part: the rules at service areas and the logic of batteries collide at the same number.
The Zaoyang North service area in Hubei once imposed a strict rule: all cars had to leave once they reached 80% charge. The chargers automatically limited the current. That was to make sure the people behind them could charge too. A driver might want to stop at 90% so the car can recapture some of that downhill energy. The reasons are completely opposite. The numbers they land on are almost the same. One says, “You’ve had enough—move along.” The other says, “I’m not full yet, but I can’t be too full.”
And yes, charging really does slow down. It’s clear where the slowdown happens. Wang Chuanfu has said the hardest part of charging to improve is the final 20%: the closer you get to full, the faster the charging rate drops.
Expressway service areas across the country have installed a total of 89,000 charging connectors. Of these, 62,700 are included in monitoring. On the first day of the National Day holiday, they delivered 28,046,900 kWh of electricity—60% more than the same day last year, a new record.
Capacity designed for normal traffic ran into a peak that was nearly twice as high, and the queues stretched back to the service area entrances. There was no way to calculate around it. No easy fix. So what, exactly, did that half hour buy you?
There’s an equivalent idea in blockchain. Ethereum blocks were never designed to be used to capacity: the target is half the maximum. When actual usage exceeds the target, the base fee goes up, by at most 12.5% per block. That half is left open not to waste capacity, but to provide a buffer for sudden surges. In their view, a full block is a price signal, not the normal state of affairs.
As for how much room to leave, different people have different answers. Some drivers report that regenerative braking only gradually comes back once the battery drops to somewhere between 92% and 98%; exactly where depends on the model. Some manufacturers don’t let you choose at all: they fix the regenerative braking strength and use mechanical brakes to provide the same deceleration. I couldn’t find a universal standard. I’ve thought about it for a few days, and the truth is, every manufacturer calibrates its electronic controls differently.
Next time you’re at a service area and see someone wait two hours just to charge to full, don’t rush to laugh and assume they can’t do the math. They’re buying those few dozen extra kilometers on the dashboard, and paying for it with brake pads on the downhill stretch. If you’re really driving in the mountains, bring the charge down to 80–90% before you start climbing. That isn’t saving electricity. It’s leaving the motor some room to put energy back in.
$BTC $ETH $LINK
#电动车 #动能回收 #高速服务区 #NewEnergy
At three in the morning, a Chengdu driver photographed this slip at a service area. More than a hundred cars were ahead of them. Another account from the same holiday described waiting over five hours just to plug in. They charged for half an hour.
During the National Day holiday, new-energy vehicle traffic on the expressways surged to 17.8 million—nearly twice the usual level. With so many cars in line, everyone had the same goal: get the battery fully charged.
But that’s exactly what you shouldn’t do.
A fully charged car is full at precisely the wrong time when going downhill.
When the motor slows the car, it spins in reverse like a generator, converting kinetic energy into electricity and feeding it back into the battery—but only if the battery has room to take it. Once the charge passes 95%, the battery can accept very little power. The battery management system reduces regenerative braking, or even shuts it off altogether. To prevent overcharging. To keep the voltage from getting too high. To prevent heat buildup. At that point, when you lift off the accelerator, the car coasts farther than usual and slows down sluggishly, while the dashboard displays “Regenerative braking limited.” The brakes have to do the rest.
So not charging all the way isn’t being stingy. It leaves room for regenerative braking to put energy back into the battery.
The manufacturers themselves acknowledge this trade-off. At a launch event in March, BYD set the charging limit at 97%. Wang Chuanfu’s exact words were that the remaining 3% is reserved specifically for recovering energy from braking. From 10% to 97% in nine minutes.
Here’s the interesting part: the rules at service areas and the logic of batteries collide at the same number.
The Zaoyang North service area in Hubei once imposed a strict rule: all cars had to leave once they reached 80% charge. The chargers automatically limited the current. That was to make sure the people behind them could charge too. A driver might want to stop at 90% so the car can recapture some of that downhill energy. The reasons are completely opposite. The numbers they land on are almost the same. One says, “You’ve had enough—move along.” The other says, “I’m not full yet, but I can’t be too full.”
And yes, charging really does slow down. It’s clear where the slowdown happens. Wang Chuanfu has said the hardest part of charging to improve is the final 20%: the closer you get to full, the faster the charging rate drops.
Expressway service areas across the country have installed a total of 89,000 charging connectors. Of these, 62,700 are included in monitoring. On the first day of the National Day holiday, they delivered 28,046,900 kWh of electricity—60% more than the same day last year, a new record.
Capacity designed for normal traffic ran into a peak that was nearly twice as high, and the queues stretched back to the service area entrances. There was no way to calculate around it. No easy fix. So what, exactly, did that half hour buy you?
There’s an equivalent idea in blockchain. Ethereum blocks were never designed to be used to capacity: the target is half the maximum. When actual usage exceeds the target, the base fee goes up, by at most 12.5% per block. That half is left open not to waste capacity, but to provide a buffer for sudden surges. In their view, a full block is a price signal, not the normal state of affairs.
As for how much room to leave, different people have different answers. Some drivers report that regenerative braking only gradually comes back once the battery drops to somewhere between 92% and 98%; exactly where depends on the model. Some manufacturers don’t let you choose at all: they fix the regenerative braking strength and use mechanical brakes to provide the same deceleration. I couldn’t find a universal standard. I’ve thought about it for a few days, and the truth is, every manufacturer calibrates its electronic controls differently.
Next time you’re at a service area and see someone wait two hours just to charge to full, don’t rush to laugh and assume they can’t do the math. They’re buying those few dozen extra kilometers on the dashboard, and paying for it with brake pads on the downhill stretch. If you’re really driving in the mountains, bring the charge down to 80–90% before you start climbing. That isn’t saving electricity. It’s leaving the motor some room to put energy back in.
$BTC $ETH $LINK
#电动车 #动能回收 #高速服务区 #NewEnergy