Adding energy storage reflects the evolution of the company, which started off as a solar cell and panel maker before it entered the power plant development business. SunPower has carried out pilot energy storage projects in recent years and worked with different energy storage technologies, including advanced lead acid and zinc bromide batteries.

But lithium-ion batteries “will likely be the first technology to have an impact,” said Jack Peurach, executive vice president of products. The emergence of electric cars plays a role in making lithium-ion battery the front runner for being paired with solar, he added.

SunPower & Flextronics Factory in Milpitas, CA

SunPower executives didn’t provide details, such as the timing and battery suppliers, for its energy storage plans. But the discussion puts SunPower on a growing roster of solar energy companies that are offering or plan to offer energy storage.

SolarCity, for example,  has been bundling lithium-ion batteries from Tesla Motors with its solar energy systems and applying for a California program that subsidizes energy storage installations. One Roof Energy is working with battery maker Silent Power to roll out products. Korean conglomerate Hanwha Group, which runs a solar panel manufacturing subsidiary, is an investor in both OneRoof and Silent Power. SunEdison has done a pilot project with a battery system from startup Seeo.

Energy storage will be part of SunPower’s plan to expand its reach in the commercial and residential market, where it sells power purchase agreements or leases via its dealers or its own project development business. The company designs the power purchase agreements for its commercial and government customers and leases for homeowners. Power purchase agreements and leases work in similar ways: business or home owners sign a long-term contract of up to 20 years and pay a monthly fee for the solar electricity from the SunPower solar energy systems on their rooftops.

SunPower’s foray into the energy storage business will prompt more comparison with SolarCity, which started in 2006 as purely a solar installer. SolarCity is most active in the residential and commercial markets, but it scored the first utility project last year. As a result, the two companies have been competing more intensely in recent years.

In fact, a lawsuit filed by SunPower against SolarCity and five people last year highlighted that rivalry. The lawsuit accused five former SunPower employees of stealing confidential data and brought the data with them when they went to work for SolarCity. The two companies settled on Dec. 31, 2012, and a judge dismissed the lawsuit in January, SolarCity said in its 2012 annual report. It didn’t disclose the amount of the settlement.

SunPower executives didn’t say whether they will sell energy storage in the United States first or in other regions. Werner said that, for now, energy storage makes financial sense only in markets that offers government incentives. That would include California, Germany and Japan.

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While the Evanston, Ill.-based startup is only a year old, it’s made some substantial progress this year, and this month SiNode Systems won over $900,000 in the Rice Business Plan Competition. The startup is now working on raising an additional $1.5 million to bring its technology out of the lab, Guy Peterson, director of commercialization and manufacturing at SiNode, told us in an interview.

SiNode Systems is building on research developed by Northwestern Professor Harold Kung, whose work focuses on the use of a composite of silicon nanoparticles and graphene for the anode part of a battery. A battery is made up of an anode and a cathode and an electrolyte in between, and electrically charged lithium ions flow between the anode and the cathode to discharge or charge the battery.

SiNode’s core intellectual technology involves creating a porous structure in the graphene to speed up the movement of electrons between the anode and the cathode and to stabilize the silicon, creating a sort of scaffolding around it. Silicon swells and contracts quickly and could fall apart easily without a supporting structure.

Lithium ion batteries on the market today typically use graphite for the anode. For the cathode, cobalt oxide is commonly used for consumer electronics while other compounds, such as iron phosphate and manganese oxide are also found in electric cars and power tools.

Lab work has shown that SiNode’s technology could lead to an anode with roughly ten times more energy capacity than the conventional graphite anode, said Guy Peterson, director of commercialization and manufacturing at SiNode. A higher capacity will create a battery that can keep your mobile phone working longer before you have to charge it.

So what does a better anode mean for the overall energy capacity of the battery, which is ultimately what battery retailers and consumers would want to know? Peterson declined to say, partly because the company is still working on that number.

The graphene structure also makes it possible to cut the charging time of the anode by about 10 times compared with the typical charging time of a smart phone at home, Peterson said.

A promising technology needs to marry a low-cost manufacturing process to find success in the market, especially when the technology is targeting the consumer electronics market and there is no shortage of major battery makers and startups working on using silicon and other compounds to improve the anode’s performance (see our list of 13 battery startups to watch).

Peterson said SiNode is working on a production process that promises to be less complicated than some of the existing methods. The process creates a sheet of material at the end rather than a powder.

“A lot of competitors take two steps forward in performance and four steps back in scalability,” Peterson said. “We can offer performance and scalability.”

SiNode plans to supply the anode material or license its technology or both. The company is still working on its business model and manufacturing plans.

From the Rice competition, the startup is set to receive $700,000 in equity investments, $110,000 in cash and $101,400 in office space, marketing and other business services. Before the competition, the company had raised just over $200,000.

Photos courtesy of Northwestern University

Updated at 3:30 PM on April 29, to correct that the technology boosts the amount of energy that a battery’s anode can hold, it does not boost the amount of energy that a battery in general can hold.

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Six-year-old startup Seeo — which is backed by Vinod Khosla, Google.org and others — has installed its first battery system to act as energy storage in conjunction with a solar panel system developed by SunEdison, according to Seeo CEO Hal Zarem, who I interviewed last week. The solar battery installation is a trial for now, but a sizable one: on the level of kilowatts and tens of kilowatts, explained Zarem. For comparison’s sake, the Nissan LEAF uses a 24 kilowatt hour battery, while an average cell phone will use 2,000 to 3,000 milliamp hour batteries (far smaller than a kilowatt hour of capacity).

Batteries, like the one Seeo has installed for SunEdison’s solar system, can act as storage for the energy produced by solar panels, so that when the sun goes down (or behind a cloud) the battery can then offer up the stored power. Utilities, building owners and even home owners are starting to see the benefits of having battery storage systems connected to solar systems, because power can be far more smooth and reliable. Likewise solar installer SolarCity has been working with Tesla’s batteries to sell a home battery system with its solar panels in certain markets.

The next-gen tech

So what makes Seeo’s batteries safer? It largely involves improvements to the electrolyte, or the medium that shuttles lithium ions back and forth between the cathode and the anode to charge and discharge the battery. Traditional lithium-ion battery electrolytes are mostly made of liquids, while Seeo is using a solid dry polymer based electrolyte, which feels like plastic to the touch.

The polymer is non-flammable and when combined with using lithium foil as the anode, the battery can be ultra light weight and also have a high energy density, or amount of energy that can be stored per a given weight. During an interview at Seeo’s headquarters last week I picked up and compared two battery packs — one made by Seeo, and one that used traditional lithium ion batteries — and the Seeo battery felt about three times lighter.

If traditional lithium ion batteries are overcharged they can have a margin of error in the danger zone of about 20 percent above the max voltage of the battery, explained Zarem. In contrast, Seeo batteries have a margin of error of 100 percent over the voltage. The batteries also won’t burst into flames if something penetrates it (for example, during a car crash).

Seeo isn’t the only one working on solid electrolytes for batteries. It’s actually a growing field for innovation, and startups like Sakti3, and Imprint Energy are working on this technology, as are researchers at Oak Ridge National Laboratory.

What’s next

Seeo has just started commercializing its technology and working with customers to test out its batteries. The company has built out a pilot production line at its headquarters in Hayward, Calif., which can make 4 MW hours worth of batteries using traditional manufacturing machines like coaters. I toured the company’s pilot line last week and the team is indeed heads down churning out small levels of Seeo batteries.

But to get to the next-level of manufacturing, which involves hundreds of megawatt hours — the kind that could start to actually change the game for solar energy storage, or electric vehicles — Seeo plans to build a new factory somewhere in the U.S. this year, close enough to the Hayward site to create easy collaboration. It could end up being built in Hayward, says Zarem, but the company is still in the process of figuring out the best location.

Seeo could have to raise some sort of funding to get such a plant built, and probably has already started raising such funding. But on that funding note Zarem wouldn’t comment. Raising funding could be difficult in 2013, after so many advanced battery companies, like A123 Systems, struggled in 2012. Eventually Seeo also wants to build an even larger plant, but that would likely be developed outside of the U.S., in a low cost manufacturing part of the world, said Zarem.

Along with Google.org, and Khosla Ventures, Seeo also has investors Chinese firm GSR Ventures, and Presidio Ventures, a fund managed by Japanese giant Sumitomo. So clearly, Seeo has some strategic connections in overseas markets.

Seeo’s Zarem has an interesting perspective on the past couple of years of battery innovation. A generation of large battery factories were built out in recent years, he said, some using U.S. government funds to meet an anticipated market for electric cars (like A123 Systems). Unfortunately that electric car market didn’t emerge as quickly as expected, but it’s coming, as is energy storage for clean power.

Sometimes the companies that are the first to market either aren’t the right ones, or they’re too early, says Zarem. Of course, he’s hoping that Seeo has timed it just right.

This article was updated at 10:15AM to correct that the company has an investment from Google.org, instead of Google Ventures.

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Leyden Energy was founded in 2007 (formerly called Mobius Power) with a patent acquired from chemical giant Dupont, and a $4.5 million investment from investors. Leyden’s original secret sauce is an innovation for the electrolyte part of the battery. A battery has a positive and a negative plate and then an electrolyte in between, which is the substance through which electrons transfer back and forth while the battery charges and discharges.

In addition to its electrolyte innovation, Leyden also has a new breakthrough technology for a silicon anode that boosts the energy density (amount of energy stored per volume) and enables the battery to be made in a very slim form factor. Many battery companies combine next-generation technology in each part of the battery to produce a better whole battery in production.

Making lithium ion batteries slim is a priority for Leyden. It’s recently been focused on tablets and consumer electronics and announced an effort with chipmaker NVIDIA to design tablets; it also has been courting makers of chargers for smart phones and devices for personal Wi-Fi hot spots. A couple years ago Leyden launched a replacement lithium-ion battery for laptops that won’t degrade (start losing its full charge) for at least three years, and will come with a three-year warranty.

Start-stop vehicle tech, which uses a battery to automatically cut off the engine of a gas-powered vehicle while it’s idling, is another target area for Leyden. Start-stop vehicle technology is starting to gain momentum in Europe, following carbon reduction regulations, and the technology can reduce fuel use by 5 to 12 percent.

These are difficult times for battery startups right now, particularly those that were hoping the electric car market would take off faster than it has. Lithium ion battery leader A123 Systems recently went bankrupt and then was sold to Chinese auto parts giant Wanxiang. Battery maker Ener1 also filed for bankruptcy last year.

But there’s still some rare next-gen battery startups looking to innovate around new materials, new production techniques, and nanotechnology. Here’s 13 battery startups to watch in 2013.

Leyden’s series C round of $10 million came from existing investors including NEA, Lightspeed Ventures, Sigma Partners and Walden International. The company has raised $48 million in venture capital since it was founded.

Images courtesy of Leyden Energy.

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The winning bid beat out Johnson Control’s bid to acquire A123′s automotive division. Johnson Controls previously had offered to buy the automotive division and two factories for $125 million.

One of the reasons Wanxiang’s offer to buy up A123 had been controversial was because A123 had some U.S. military contracts, which critics didn’t want to see in the hands of a Chinese company. But A123 decided to sell off its government business, including all its U.S. military contracts, to Illinois-based company Navitas Systems, for $2.25 million. Wanxiang acquired the rest of the assets including the grid storage business.

We’ll see if that move silences politician critics like U.S. Sens. John Thune (R-S.D.) and Charles E. Grassley (R-Iowa). The deal still has to be approved by the bankruptcy court as well as the Committee for Foreign Investment in the United States (CIFIUS).

If approved, the future of A123 System’s lithium ion battery tech will fittingly be owned by a Chinese auto giant, as China is increasingly becoming one of the most important markets for electric vehicles. Money from Chinese investors, conglomerates, cities and the government, continues to drive a significant amount of the future of next-generation electric car technology.

The deal also provides a future for A123′s technology, which had a promising beginning, but had suffered a series of setbacks in 2012. Venture-backed A123 held the largest IPO in 2009, raising some $371 million, and was trading at over $20 per share when it started trading. A123 also raised more than $350 million from private investors when it was still a startup.

Yet in recent months, it suffered from manufacturing problems, and also had only a handful of customers for its premium batteries. The company had been losing boat loads of money for years.

The Wanxiang deal still won’t make back enough to cover its debts. A123 says:

Because the total purchase price for A123’s assets would be less than the total amount owed to creditors, the Company does not anticipate any recoveries for its current shareholders and believes its stock to have no value.

Now that the A123 bankruptcy is moving forward, it will be interesting to see what Fisker Automotive, one of A123′s prime customers, will do. Fisker had told the media that it is waiting for the results of the A123 auction before it starts back up assembling its Karma cars.

This isn’t Wanxiang’s first cleantech and clean energy acquisition — it’s actually its fifth in 2012, says the company in a release. Wanxiang has been aggressively acquiring under valued American cleantech and clean energy companies.

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If you haven’t been following this story, Wanxiang originally had a deal to buy up to 80 percent of A123 Systems for $450 million if A123 met certain conditions. Either those conditions weren’t met — or A123 grew worried that its deal with a Chinese conglomerate might face hurdles — because a few months later that deal fell through and A123 declared bankruptcy. The auction today will determine what happens to A123 post-bankruptcy.

Here’s why the prospect of A123 being sold to a Chinese firm has been raising eyebrows:

A123, once a promising battery maker that held one of the largest cleantech IPOs back in 2009, was awarded a grant from the Department of Energy for $249 million, and A123 drew down on $132 million of that grant. So the U.S. government put substantial money into developing this technology. In addition, A123 has had contracts with the U.S. military.

Both of these aspects have made a sale of A123 to Wanxiang distasteful to some politicians, like U.S. Sens. John Thune (R-S.D.) and Charles E. Grassley (R-Iowa). They’ve written letters on the subject and asked for a sale to Wanxiang be blocked. To add kindling to the fire, electric vehicles — and cleantech in general — have become a politicized issue, with high profile Republican politicians rejecting the support of electric vehicles, and Democratic ones embracing support for the technology.

Meanwhile, electric car startup Fisker Automotive, which has also been the subject of much politically driven criticism, has been a  major customer of A123′s batteries. So it is waiting on the result of the bankruptcy case before it figures out what to with the assembly of its cars. By the way, Fisker deserves a lot of criticism, but not for building its first car in Finland, which is what politicians have been upset about.

Fears of Chinese tech companies swooping in and buying up beleagured U.S. assets is at the heart of this issue. The discussions of the military contracts, and the misplaced grants from the DOE are side notes, which can be addressed independently. The reality is that China using the U.S. as a discount shopping mall is only going to continue to grow. Wanxiang has been — smartly or not — shopping for low valued energy, cleantech and electric car assets in the U.S. That’s how global capitalism works and in recent years has increasingly been working in the U.S. and China.

A123 should be allowed to find the best deal for its assets and shareholders regardless of the country. The potential acquirer that values the technology the highest, and is willing to pay the most, should win the bidding.

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It’s not just those who gunned for the electric car, or even the emerging power grid market, that have experienced disappointment and shifted their focus. Wilmer tells us that Leyden has tweaked its plans over the past year, and is now focusing on the tablet market as well as providing batteries for gasoline cars with start-stop technology. Previously the startup was looking to sell batteries for laptops, and electric bicycles, and then wanted to move into newer and tougher ones like electric cars.

Leyden had a deal with distributor Dr. Battery to sell cylindrical cell batteries, like the AA batteries in a flashlight, which it announced last year. But the company is no longer selling to Dr. Battery, said Wilmer, who became Leyden’s CEO earlier this year. The laptop market isn’t showing enough growth because consumers prefer thinner notebooks or tablets, and cylindrical cells also aren’t in demand for e-bikes, said Wilmer. UPDATE: Dr. Battery’s CFO,  Fan Chun, told me that his company’s relationship with Leyden hasn’t ended. In fact, Leyden is still shipping cylindrical cells to a contract manufacturer hired by Dr. Battery to assemble the cells into battery packs.

But the company has been working on developing flat and rectangular pouch cells that fit into slimmer consumer electronics. Leyden more recently has announced an effort with chipmaker NVIDIA to design tablets, which they hope will catch the eyes of tablet makers. Leyden also is courting makers of chargers for smart phones and devices for personal Wi-Fi hot spots. The company is shipping its battery cells to customers, who have put those cells in consumer electronics, but Wilmer declined to disclose the brands or types of gadgets.

Leyden also is hoping to see its batteries in gasoline cars outfitted with stop-start technology, which use a battery pack to keep the air conditioning, radio and other electronics running while a car stops momentarily, say, at an intersection when the light turns red. The battery also kick-starts the engine after the light turns green. This technology could lead to 5-10 percent better fuel economy and lower tailpipe emissions and is starting to show up in Europe.

With the slow roll out of electric vehicles, going after more mature and reliable markets certainly makes a lot of sense. But competition in those segments already is intense. A123 also targeted the stop-start market and designed a battery pack for it. And there are non-lithium ion battery developers who are pushing their way into this still niche opportunity.

Then there is the question of how startups can compete with battery giants such as Panasonic and LG Chem who have long established their presence in the consumer electronics business and are no less interested in putting their products in cars. Incidentally, Sony apparently is looking to sell its lithium-ion battery business because it’s having trouble competing with other large battery makers, particularly those in Korea, Reuters reported. Panasonic also isn’t doing so well with its lithium-ion battery business.

The prospect will probably not get too much rosier for battery startups in the near future. Boston-Power, for example, has transformed itself into essentially a Chinese company, to take advantage of low cost financing and Chinese domestic markets. So the question is how many more battery developers will follow A123 into the bankruptcy court or get scooped up, perhaps cheaply, before reaching that point?

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Johnson Controls will also provide A123 Systems with $72.5 million to continue its operations at these factories, which will continue to produce batteries. The Department of Energy is already on top of the story, and sent me points stating that “A123 has only used $132 million of its 2009 grant (in addition to the $6 million from the Bush Administration.)” The bankruptcy will be sure to be controversial, and perhaps we’ll even hear about it in the second round of presidential debates tonight.

I’m not exactly sure what the status of A123 System’s deal with Wanxiang is at this point. The Chinese conglomerate announced a deal in August that said it planned to invest up to $450 million in A123, for an 80 percent ownership of the firm, if certain conditions were met. I’ve emailed Wanxiang to see if that deal has been abandoned. Seems like the deal would be off if Johnson Controls is buying up much of the assets.

Bloomberg notes that A123 has listed assets of $459.8 million and debt of $376 million as of Aug. 31 in its Chapter 11 documents filed in U.S. Bankruptcy Court. A123′s stock plummeted this morning by 73.50 percent to 6 cents. A123 went public in 2009, with its shares opening at $17 per share and closing at $20.29 per share on the first day of trading.

A123 has been bleeding cash for months. One of the problems was that in March A123 announced that it would start replacing battery packs with defective cells made at its Livonia, Mich., factory. That mistake cost the company $51.6 million in warranty costs during the first quarter and another estimated $15.2 million for replacing defective batteries that were in its inventory. A123 had to replace these defective batteries in its electric car maker customer Fisker Automotive’s inaugural cars.

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The network will test out solar power, energy storage and electric grid management and produce data and analyses over the next six months, said Japanese solar panel maker, Kyocera, which is taking part in the project. The project also involves the New Energy and Industrial Technology Development Organization (NEDO) of Japan, Los Alamos National Laboratory and the Los Alamos Department of Public Utilities. NEDO itself is a group of government, research institutions and private tech companies such as Kyocera, Toshiba and Hitachi.

The participants held a ceremony this week to kick off the operation of the $52 million project, which involves a micro-grid and a “smart house” demonstration in Los Alamos. The Japanese consortium also is working on a smart building project in a mixed-use community in Albuquerque called Mesa del Sol.

NEDO and its affiliated Japanese companies decided to head to New Mexico to test smart grid technologies with the local utility in Los Alamos partly because Japanese utilities aren’t as flexible or able to act as quickly to accommodate the project, according to this 2011 presentation by the Los Alamos utility company. The Japanese companies also want to sell their technologies in the U.S. and take an active role in setting international technical standards for smart grid. The Los Alamos lab will help with data collection, management and modeling.

The consortium conceived of the project a few years back and signed an agreement to carry it out in 2010. While the goal back then included an intent to tackle the U.S. market, the results from the project could serve Japan as well, particularly since the country has been keen on boosting renewable energy generation ever since its Fukushima nuclear plant disaster in March 2011. Kyocera, for example, earlier this year announced a plan to sell solar energy systems with batteries to homeowners in Japan.

Adding more renewable energy into the grid presents technical and operational challenges for utilities and grid operators. Solar and wind power, for example, can only be generated at certain hours of the day and night, and weather conditions have a big impact on their production rates. Since an electric grid works best when there is a balance of supply and demand, grid operators have to figure out how to make up for any short fall or surge of renewable energy that could happen at any time. Power plants that use coal, natural gas and nuclear, on the other hand, can produce a steady stream of power.

Many other utilities and tech companies are carrying out similar demonstration projects in the U.S. in order to meet their state mandates to increasing the use of renewable energy.

One of the two projects underway within Los Alamos utility’s territory creates a micro-grid using a 1 MW solar energy system and a 1.8 MW/8.3 Mwh battery system. The solar energy will course through a particular distribution line to test its impact on the grid.

The second project will put solar panels on a home, which has been built especially for the project (check out the Los Alamos Daily Post’s report), and pairs the solar system by Kyocera with a 24 kWh lithium-ion battery system, a heat pump storage unit, and sensors and communication equipment. The idea is to figure out how to operate all this equipment to meet the energy demand of the home and respond to any requests from the utility or grid operator to use the solar electricity for balancing the grid.

Photo courtesy of Kyocera

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The trade show and conference is expected to attract over 22,000 attendees over the next four days. Aside from the usual deep dive into various types of solar technologies, regional market analyses and project financing models and policies, there will be a series of panel discussions on energy storage technologies and how to pair them with solar energy projects.

Solar panel maker Hanwha SolarOne announced Monday that is has invested $8 million in a B round for Silent Power, an energy storage equipment company in Minnesota. With the investment, Hanwha plans to market a package of its solar panels with Silent Power’s energy storage products for residential and commercial markets. The companies expect to launch their first product by September this year. Silent Power says it can use different types of batteries – from lithium-ion to lead-acid – to build its battery systems.

Energy storage systems are handy because they can serve several purposes, from banking solar power for later use to balancing the supply and demand of an electric grid. That’s the concept, at least. Given energy storage isn’t widely used, energy storage tech companies still need to demonstrate, usually through pilot projects, that their equipment and software can perform as promised over time. Some of the energy storage technologies, such as the use of advanced batteries, also remain too expensive for mass adoption.

Given the high price tag, the conventional belief is that energy storage will take off with larger clean power projects first. Eventually, it will be cheap enough where it will show up at homes that have solar panels on their roofs.

Already, we have seen more co-marketing partnerships between solar and energy storage companies for the residential market over the past year. We wrote about SolarCity’s quiet marketing of solar panels and Tesla Motors’ battery systems to take advantage of an incentive program in California a few months back. Solar panel maker Kyocera is teaming up with Nichicon to roll out a set of solar energy system-cum-battery products for the Japanese market. The Fukushima nuclear power plant disaster from a year ago generated a heightened interest in solar energy and backup power systems.

Energy storage won’t be the only key theme at Intersolar, which showcases manufacturers of a variety of solar energy equipment. Solar manufacturers have been experiencing tough times since early 2011, when an oversupply of solar panels began to cause their prices to crash. What will it take to get through this period, which isn’t ending as quickly as many companies had anticipated? That will be the underlying theme for many of the discussions.

To underscore the impact of this gross imbalance of oversupply and demand, we are updating our list of solar companies that have filed for bankruptcy since 2011:

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