Changxing accounts for more than 45 percent of the lead-acid battery production in China. [Yan Yiqi / China Daily]

The efforts by the county officials saw the industry focusing on developing lead-acid batteries for electric cars, military vehicles and solar and wind power storage. That, in itself, was a major change considering that most of the companies were largely reliant on making lead-acid batteries for electric bicycles, products that were not so common in the international markets.

"Although the domestic market for electric bicycles still holds great potential, the idea of moving ahead on a green growth path excited us," Wang says.

Such efforts have started paying off and it is not so uncommon to see dual-powered streetlights in Changxing, with both fans and solar panels on top and a set of batteries nearby. So much so the city has become a major testing ground for lead-acid batteries used in new energy.

"The battery industry is closely related with the energy field. Since batteries can store electricity that provide power to vehicles, they can also be used to store the unused electricity produced by solar and wind power," says Yao Lingchun, deputy secretary-general of the China Refractory Industry Association.

"Many people consider lithium batteries to be lighter and cleaner than lead-acid batteries. But I believe that lead-acid batteries are irreplaceable for at least 20 years due to their stability and safety," he says.

Currently, eight battery companies in Changxing have started solar photovoltaic production with total investment of 15.1 billion yuan and an estimated output value of 23.4 billion yuan. When completed, they can produce battery sets that can store over 1,000 mW of solar power.

Prior to 2005, most of the lead-acid companies in Changxing were family-owned workshops. The manufacturing techniques used were mostly basic and as such there were hardly any effort to address issues like environmental pollution.

Matters came to a head in 2005 when a group of residents accused Tianneng Group, Changxing's largest battery company, of polluting the neighborhood. Not long after this came the incidents of high lead content, revealed during blood tests, in children near the factories.

Changxing resident Liu Fuxiu still remembers the violent protests of that period, but admits that things have changed now.

"It is totally different from what it was then, especially in the areas where the battery factories are located. I am glad everything has changed," she says. Nearly 125 of the more than 175 battery factories in Changxing had to exit the business or move on to other areas due to the incidents of 2005.

"I used to hate the government for forcing us to shut down the company. Later, I discovered that the threshold for the industry was no longer as low as before, and it was better for me to opt out," says Zhou Fuming, whose battery company was closed in the 2005 movement and is now the owner of a high-end home textiles company.

But for the remaining companies, the environmental challenges inspired them to develop on a broader scale.

"Most people have the tendency to equate lead-acid battery industry with polluted water and lead fumes, especially so as improper management of lead and sulphuric acid can cause air and water pollution. I would ask the critics to come and judge for themselves as to whether it is the case now," Wang says.

"It is not so and it is only going to get even better," Wang says, referring to the new environmental standards introduced by the local government adding that they are stricter than the national ones.

"Our standards are three times stricter than the national ones in terms of maximum emission of both wasted gas and water," says He Xinzhong, deputy director of Changxing Environmental Protection Bureau.

The regulations, including stipulations that factories should be built only in the areas where there are no residents within 500 meters, and released by the bureau in August, reinforced the city's determination to improve industry discipline.

"The first step was to close unqualified factories for good," says He.

At that time, Changxing had some 61 lead-acid battery companies, and nearly 34 of them were shut down after they failed to meet the stipulated norms, while 13 were forced to relocate their factories.

The relocated companies will be housed in a new battery industry park, which will more or less be a relatively closed facility on the outskirts of the city. Before moving into the new factory buildings, only the charging and assembly sectors of the companies can operate.

"This is a difficult process, as it means that more than half the companies would have to leave the industry, while the balance cannot do any kind of manufacturing until they move into the new premises," says Wang.

Deqing Haijiu Battery Co was one of the companies that had been shut down during the movement, because it failed to reach the required emission standards. Though the company had already announced its listing plans, the local government was in no mood to give any concessions and stuck to its plan of cleaning up the industry.

"Forcing such a company to close down is definitely a rare practice in China. But we did it," Wang says.

Though there were protests from some factory owners initially, the local government was also equally determined to clean up its image. The government paid compensations to the closed companies and also to those who have been relocated.

"Although most of the battery companies have their production bases outside Zhejiang province, 2011 sales revenue of the whole industry in Changxing remained flat. Prior to that the industry had always seen average revenue growth rates of around 30 percent," says He.

Wang expects the industry to be back on the growth track in 2013 when the planned production centers become operational.

"Our goal is to upgrade the industry as a new-energy destination," Wang says.

Closing up small and unqualified companies was just one of the steps taken by Changxing to improve its battery industry.

"Apart from pollution caused by manufacturing processes, there were also growing concerns over the improper disposal of used batteries. To solve this issue, we have started to promote battery recycling programs," says Yao.

According to Yao, the recycling rate of China's lead-acid batteries is as low as 30 percent, but the same can be 90 percent in the United States.

"More than 80 percent of lead produced in the US is used in lead-acid batteries and 98 percent of all battery lead and plastic is recycled, demonstrating the enormous impact battery manufacturers have on the upkeep of the safe and clean environment," says Randy Hart, president of Battery Council International.

Battery Council International has been instrumental in promoting the enactment of lead-acid battery recycling requirements that are legally binding in 43 US states.

"China must enact national regulations to promote recycling of such batteries so that the industry will not be so resource and environment-consuming," says Yao.