I heard , that the Twizy is build for a 5 year lifetime.
(Usual for a quad) So all materials are choosen accordingly.
If you take care of it then it will last longer.
But the rental scheme is calculated for that timeframe
5 years will cover the cost of the battery and service/overhead.
(In 2012 that was. Now they surly make a profit after 5 years. )
If your twizy lasts longer or you decide to drive more than 10000km a year they make a surplus.
We need a commercial alternative to the renault battery.
The protocolls are in the open now and free to use.
If the market hits a critical mass renault will react.
How this will act out in the end is another question.