Maintenance

From Apterawiki

Contents 1 Common tasks 2 Batteries 3 List 4 The numbers 5 See Also

[edit] Common tasks

The hood of the Aptera opens down, not up, for maintenance[1].

Maintenance needs differ between the Typ-1e and the Typ-1h. The Typ-1h, having a small gasoline engine, has the typical maintenance needs of such an engine, although one can expect it to be used less in total due to the electric range. Both contain an electric drivetrain, and this drivetrain is all that the Typ-1e has.

Electric drivetrains have a tiny fraction as many moving parts and thus keep maintenance to a minimum[2]. There's not even any motor oil to change, and often no transmission (as is the case with the Aptera, which uses a fixed gear ratio belt to connect the motor to the drive wheel). The belt will likely wear over time and have to be replaced on occasion, just like any other belt. Due to most braking being regenerative, the front disc brakes will experience less use, and thus less wear. The light weight of the vehicle will also reduce brake wear. Low rolling resistance tires tend to wear faster than normal tires; this should be offset by the light weight of the vehicle. The tires tend to be more expensive. Only three are needed.

[edit] Batteries

There is a common notion that all batteries are like lead-acid -- toxic and with short lifespans. Nothing could be further from the truth. Even at the turn of the 20th century, when early EVs such as the Baker Electric began being produced in bulk, this wasn't the case. The Baker Electrics used long-lifespan nickel-iron batteries, and surviving vehicles often still run on their original batteries.

The Aptera is to use off-the-shelf lithium phosphate batteries.[3] The most common kind of these is lithium iron phosphate. These batteries have now, for several years, been powering cordless power tools and are widely replacing lithium polymer batteries in RC aircraft. Compared to traditional lithium ion batteries, they lose a good chunk of the energy density, and are often around 100Wh/kg. They retain its other beneficial properties -- extreme efficiency, and high power density (LiP is actually several times higher). They gain fire resistance, fast charge capability, extreme longevity, and are largely nontoxic. Even in high load usage (which shortens lifespan), such as in RC aircraft, LiP batteries display little loss in charge capacity after many cycles.[4] A123's lithium phosphate batteries have already been tested to 7,000 cycles[5] which, for a Typ-1e, would be 840,000 miles.

Given that GM has suggested an approximately $10,000 price for the Volt's 18kWh pack (with one of the competing suppliers using lithium phosphate cells), this would suggest a price of about $0.56/kWh. This is more expensive than conventional laptop batteries; however, the price is almost exclusively due to a lack of mass production. For traditional li-ion batteries in an automated factory, material costs make up 78-80% of production costs[6], and the most expensive element by far is the lithium cobalt oxide cathode. Lithium phosphate batteries have a completely different cathode, made from reducing lithium carbonate with phosphoric acid and binding the particles with carbon from sugar.[7] All of these ingredients are incredibly cheap; however, the process has not been scaled up with the sort of large-scale automation found in traditional li-ion production.

At current pricing, the Typ-1e's 10kWh pack would cost $5600, and the Typ-1h's a fraction of this. If we assume that the battery pack for some reason was damaged or died ten years down the road, one wouldn't expect more than $0.20/kWh or so, which would be about $2000 (and less for the Typ-1h).

[edit] List

Both Typ-1e and Typ-1h (in approximate order of frequency):

1. Maintain tire Air Pressure
2. Clean the Windows and the glass over the Solar Panel
3. Clean and preserve the exterior surface finish
4. Check or replace Windshield wiper Fluid and Wipers
5. Possibly clean the Heat-Pump's two Condensers
6. Clean or replace the cabin Air Filter
7. Check Brake System Fluid, and check for leaks
8. Check for tight battery and other Electrical Connections
9. Replace Brakes and Tires as needed
10. Others ??

Type-1e Only:

1.  ??

Typ-1h - Gas-driven Generator maintenance:

1. Add fuel, possibly drain "very old" fuel first.
2. Check and maintain coolant level (antifreeze?)
3. Change engine Oil and Oil Filter (based on engine-hours?)
4. Change engine Air Filter
5. Possibly bearing lubrication on the generator
6. Others ?

Note: The above list is approximate, not an exhaustive or complete list.

[edit] The numbers

These numbers are speculative at this point; hard numbers will not be out until the Aptera has experienced significant road testing, so any numbers you see here should be taken with a grain of salt. For a Typ-1h, add the cost of servicing a small, infrequently used gasoline engine. Let's assume that the car lasts 20 years (a few years longer than your typical vehicle today) due to the low maintenance and operation costs. Estimated labor costs will be included.

• Brake pads/rotors: $150 every 5 years (All three wheels have disc brakes, and they'll get little wear because of the light weight and regenerative braking)
• Tires: Potenza RE92s are about $65 each. We'll say $250 every 3 years (35-40k miles) for the three tires plus ~$40 for a rotation or two (only three tires, so perhaps a little cheaper than usual) in the interrim. We'll call it ~$125/year.
• Drive belts: Motorcycle drive belts, which these appear to be, cost around $100 to $220, and should last about 4 years (~50,000 miles). We'll say $160 per belt. $320 for 2 belts every 4 years plus $80 in labor -- $400, i.e., $100/year.
• Motor/inverter/gearbox: Let's assume that 30% of the cost of this needs to be replaced not under warranty at some point. Given this data, the cost of all of these parts is probably around $8,200 ($6500 plus the gearbox plus labor), so $2,460 (spread out over 20 years, that's $123/year).
• Wiring, sensors, charger, etc: $50/year average should cover this.
• Batteries: Should be warrantied for a long time. Should last the lifespan of the vehicle. To be pessimistic, let's say that the owner *does* replace the batteries, *not* under warranty, ten years down the road. By the above numbers, let's add $2,000 and $500 labor.
• Fluids: $15/year. No oil changes -- you only need to "top off" things like wiper fluid.
• Misc: $100/year. This would include things like fans, the heat pump, the StreetDeck system, cameras, windshield wipers, and so forth.

Total: $655/year, assuming a battery replacement. This is perhaps half of what you'd spend on a typical gasoline car in an average year of its life. If you assume, more reasonably, that you don't change the battery, it's more like $540 a year. For future calculations that need maintenance figures, we'll go with $550 per year to account for a small probability of having to replace the battery pack not under warranty. Just like with a normal car, an EV can be expected to have lower maintenance early on and higher maintenance later on.

To translate the above figures to per mile, we get:

• Brake pads/rotors: ~$0.0015/mi
• Tires: ~$0.01/mi
• Drive belts: ~$0.008/mi
• Motor/inverter/gearbox: ~$0.01/mi
• Wiring, sensors, charger, etc: ~$0.004/mi
• Batteries: If changed, ~$0.01/mi.
• Fluids: ~$0.001/mi
• Misc: ~$0.008/mi

Thus, we get:

• Total w/battery pack: ~$0.05/mi
• Total w/o battery pack: ~$0.04/mi (more realistic)

Electricity will add around a penny per mile to operating costs. Hence, the total operating costs per mile should be expected to be about a quarter of a relatively efficient gasoline-driven passenger sedan.

[edit] See Also

• Economics
• Cost of ownership
• Taxes