DETROIT (AP) — Electric car maker Tesla Motors delivered a quarterly record of 10,045 cars in the first quarter, helping it beat Wall Street's expectations despite costly investments in new products and factory capacity and the impact of the strong dollar.

Tesla's net loss widened to $154 million. The loss, of $1.22 per share, compared to a loss of 40 cents per share in the January-March period a year ago.

Tesla says unadjusted figures do not reflect its true performance because accounting rules limit how it records revenue for leases. On an adjusted basis, the company lost $45 million, or 36 cents per share, in the January-March period. That beat Wall Street's forecast of a 50 cent loss per share, according to analysts polled by FactSet.

Palo Alto, California-based Tesla said North American and European orders for the Model S sedan were up, but orders in China continued to lag expectations. Tesla said it remains confident it will sell 55,000 Model S sedans and Model X SUVs this year.

The company said it remains on track to deliver the Model X SUV by the end of the third quarter. Buyers should be able to start configuring their vehicles online in July, CEO Elon Musk said.

Tesla is currently building prototypes of the Model X, and in the first quarter it invested in an expanded body shop and paint shop for the Model X at its Fremont, California, factory. Musk said production volume will likely double in the fourth quarter as Model X ramps up, but he acknowledged that plan is optimistic.

"Sometimes people don't totally appreciate there are several thousand unique parts in a car, and if any one of them is unavailable, for any reason, you can not scale production," he said.

To avoid hiccups, Musk said the company is building a fleet of "several hundred" test vehicles to make sure any issues are fixed before the Model X goes on sale. The company learned that lesson in 2012, when customers who bought early versions of the Model S reported issues with door handles and other problems.

"We want to iron everything out, make sure it's good, and then deliver at high volume," Musk said.

Musk said the company hopes to reveal a prototype of its next vehicle, the Model 3 sedan, next March. The Model 3 — which will cost around half the $70,000 starting price of a Model S — will likely go on sale at the end of 2017.

On a conference call with analysts, most questions focused on Tesla's April 30 announcement that it will offer home and commercial battery packs that use solar energy to provide backup power. Production of the packs will begin soon at the Fremont factory.

Musk said worldwide demand for stationary energy storage is "just nutty," and Tesla's Powerwall home system is already sold out through mid-2016. Musk said the company's entire Nevada battery factory, which will open next year, could be devoted to stationary storage, but batteries for cars will be its priority for now.

First quarter revenue rose 51 percent to $939.9 million. Adjusted revenue of $1.1 billion beat analysts' forecast of $1.04 billion.

Shares in Tesla Motors Inc. rose 2 percent to $235.31 in after-hours trading.