Why Your Tesla Charges So Slowly
More and more complaints as to why Tesla charges so slowly are coming up on internet forums, so I did a little research.
Ever wonder why your Tesla charges so slowly? The charging speed of your Tesla depends on its three charging levels, each having configurations as to what maximum charge power they can accept. For example, the Level 1 charger using 120V outlets will fully charge your car in 4 days, the Level 2 charger on 240V outlets in 6-30 hours and with the Level 3 charger using 480V circuits, your car will be fully charged in 30-170 minutes.
While charging time can differ from one model to another, how can you get the most out of it if you’re planning to go on long drives? How true is it that older Tesla charges so slowly over time? Is it better to charge Tesla slowly or to use a supercharger?
Charging Levels That Make Your Tesla Charge So Slowly
The charging levels are determined by the level of current that flows, the level of voltage they run, and the power it delivers. Think of charging as filling up a container with water using a pipe.
Let’s say, electricity is the water, the current is the water speed, voltage is the pipe, and power is the flow of water. The higher the water speed (current) going through larger pipes (voltage), the faster the water (electricity) will flow (power) and fill up a container. In the same way, your Tesla will charge faster with higher current and larger voltage. Too bad, two of the charging levels make your Tesla charge so slowly.
Level 1: Trickle Charger
Since this charging level uses the standard 120V residential outlet, you wouldn’t expect a fast charge. It charges super slow, it was even called “trickle charging.” Normally, US drivers cover about 37 miles/day on average. But with this charger, you’ll only regain 30 miles worth of range overnight. That’s 7 miles less! And that’s just average driving.
But on the good side, you won’t pay extra for this one. A 110/120 adapter comes for free with a new Tesla car. It’s also very convenient to use since you can find standard outlets basically anywhere.
Level 2: EV Charger
This is probably the best home Tesla charger that you can get. With its compatibility to a 240V electrical outlet, you can charge your Tesla 15x faster than the Level 1 charger. It can deliver between 3.3kW and 17.2 kW of power, which enables 10-52 miles of range per hour charging.
On the downside, you may need to pay for an electrical panel upgrade to 400-amp service at your home. This will let you charge your Tesla at 17.2 kW of power on a 240-volt circuit with no worries.
But if you enjoy driving your Tesla on long rides and prefer self-charging at home rather than the supercharging stations, then this panel upgrade is a great investment. You can even choose between a regular plug-in charging or a plugless charging where your Tesla charges itself when you park over its wireless charging pad. Cool, right?
Alright, get the Tesla Gen 3 Wall Connector for utmost convenience!
Level 3: Supercharger
This supercharger can take a Tesla to 80% full in just 40 minutes. At the 80% point, your car will start to charge slowly to safeguard its battery health. You can’t install a supercharger at home but there are lots of stations located throughout the country. During your long drives, you can park at these Supercharging stations for a quick charge for your Tesla and yourself. Do some stretching and grab a bite!
Don’t Charge Your Tesla To A 100%
Tesla cars charge up to 90% by default. If you go beyond that, your battery’s longevity will shorten in the long run. Even if you want to squeeze every bit of range out of your battery, don’t charge it to 100%. Elon Musk explained that it will not only degrade your battery but will also make your car less energy efficient.
One impressive feature of this car is its regenerative braking. This technology turns braking energy into electricity, which in turn extends the car’s range by refilling the battery. There are reports that with this regenerative braking, Tesla’s range extends by as much as 30%. That means charging the battery to 90-95% might be as good as charging it to 100%.
But, how effective is it? A couple of Model S drivers reported to having captured 32% of their total energy use while driving up and down the hill. This could mean increasing 100 miles range to 132 miles. Another owner reported recapturing an approximate of 28%, while others reported recapturing between 15-20% of their total kWh usage on normal trips.
As electric cars become more popular these days, regenerative braking will eventually become common knowledge. But for now, to reap the full benefits of this trick, be sure not to charge your Tesla all the way up to 100%.
Why Older Tesla Charges So Slowly
Slow charging is already a hassle, but another problem came up this year. There are reports that older Teslas’ embedded flash memory is wearing out causing the car to charge slowly and its built-in screens to stop functioning.
Each Tesla is equipped with a flash storage chip called the eMMC embedded on an MCU1, a piece of onboard technology. This flash storage can be electrically erased and reprogrammed to help the program complete tasks quickly and efficiently. What’s happening is that Teslas are writing vehicle logs to this flash storage regularly causing the chip to stop working properly.
Phil Sadow, a Tesla repair professional, explained that Tesla creates so many logs in the car’s flash storage chip so fast that it basically burns them up. And when the eMMC burns up, you’ll just have a black, non-functioning screen on your car’s central console. You can still drive the car, but you can’t turn your climate control on or charge it. It seems like this problem appears after about 4 years of driving, so it would be helpful if Tesla “open up diagnostics” for people who may be experiencing this.
You should also check your connectors to ensure they are still in good condition. If not, just replace them with AC Connectors you can get here.
Related Questions
Is it better to charge Tesla slowly?
Charging a Tesla slowly allows more time for the heat to scatter because of the electrons moving around. Heat can degrade your battery cells, especially in hot weather.
Good thing, every Tesla is equipped with active thermal management for the battery. This will heat or cool the pack protecting the engine and keeping it in the optimal operating range. But despite this advantage, it’s much better to be extra careful in case anything happens.
What charging accessories come with a Tesla?
Tesla Model S or Model X comes with a mobile charging cord and three adapters: 1) the NEMA 5-15 you use for a standard wall outlet, 2) the NEMA 14-50 for a higher-powered 240-volt wall outlet, and 3) one used for public charging stations (with the exception of Tesla Superchargers).
Tesla also offers an upgrade from the standard charging cord. With an electrician’s help, you can install on your home a wall connector to charge your car. For a Tesla Model S battery, a wall connector can charge it fully in 6 to 9 hours, while 6½ to 10 hours for a Model X.