And because it is a subscription model, EGG-energy, not the customer, can keep track of when the batteries need to be removed from circulation. The batteries, which are designed to last around two years (150 cycles of charging and draining), could end up being a source of pollution.
"We don't want used batteries ending up in a ditch, or being burned. They have lead in them," Yang says. He notes that the company is working to ensure proper battery disposal and recycling procedures are followed.
EGG-energy currently has three charging stations on the outskirts of the Tanzanian capital Dar es Salaam. Two of them are connected to the electricity grid at the very end of the transmission lines. The third is solar-powered, and actually sits more than 30 miles from where the electricity stops.
To date, the company has wired up more than 500 homes, and sold more than 1200 subscriptions. Some of those have been to budding entrepreneurs, who buy a subscription and then begin a small business selling that power on to people who need their mobile phones charged.
The company is now working to build a network of distributors for their batteries. Ironically they are trying to tap not the same network that already distributes competing products; things like kerosene lamps, solar lamps and regular car batteries. Why not form partnerships with these distributors to deliver batteries as well, their thinking goes.
EGG-energy is hoping people will realize that their batteries are safer, and ultimately cheaper, than the alternatives. In the next year or two, the company says it will continue to build more charging stations and refine their operations. CEO Jamie Yang admits that things are moving more slowly than the company would like, but he remains convinced that if EGG-energy can create more demand for affordable and reliable in-home electricity, it could have a major effect on the entire electricity distribution chain.
"Without a reliable way to move power into homes, there's very little market for things like solar, wind and hydro," Yang tells me. "If we can move power inexpensively into homes and businesses, we can actually create a market for distributed energy generation."
"And there's no reason," he adds, "why this couldn't be a model for most of sub-Saharan Africa, not to mention parts of south and southeast Asia as well."
If you would like to comment on this story or anything else you have seen on Future, head over to our Facebook page or message us on Twitter.
