What is the real range of the Renault-Nissan Twizy and how to preserve its lithium-ion battery?

Quelle autonomie pour la Renault-Nissan Twizy et comment la préserver ?
As for all other vehicles, whether gas, diesel, electric or hybrid, the Twizy's range announced by the manufacturer Renault-Nissan does not correspond to any reality since consumption calculations are carried out in conditions no motorist ever know.
With its 7 kWh lithium-ion battery, Renault-Nissan claims that the Twizy can travel 100 km (62 mi) in standard but what is the reality? And what should we have to do to best preserve the range of an electric car?
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Four factors will play on the battery : the type of trip, the way of driving , outside temperature and loss of efficacy over time (aging) .

Type of journey and way of driving :

My personal experience rather leads to a range of 60-70 km (37-43 mi) knowing that my daily commute consists into city for a quarter and three quarters of road on which I drive at maximum speed ( 84 km/h ie 52 mi/h), but I anticipate the deceleration to best benefit from energy recovery ... A way of driving quite cool but not slow at all.
Edit 23/12/13: the use of energy recovery to stop the car is obviously a way to gain range in the short term, but is also similar to successive fast recharges which are not good for the battery life ... Nothing is simple ...
Edit 25/12/13: a member of the Renault Twizy Info forum told me that the recovery of energy occurs only below 54 km/h (ie 32 mi/h) and not exceeding 2.2 kW that is to say the equivalent of the load on a household outlet. This is good news because this system does not decrease the life of the battery!

Temperature :

Judging by the recently published Green Car Reports on the Chevrolet Volt and Nissan Leaf graph, the optimum operating temperature appears to be between 10°C and 25°C and there is a 30% drop of range when we're going to -5°C but also to +35°C. So in extreme cold or extreme heat , the Twizy's range could be reduced to 40 km (25 mi) .
However we have to keep in mind that the Volt and Leaf are equipped with heating or air conditioning , widely used in these conditions, but that the Twizy has not. Some studies rather talk about a fall from 10 to 15%, which would reduce the range of the Twizy around 50 km (30 mi) in extreme weather conditions.

Aging:

The problem of aging of lithium-ion batteries is still widely debated. If we consider that a battery becomes unusable since it has lost 20 % of its capacity, many consider that the lithium-ion batteries have a life of 8 years, but a study completed in April 2013 by Professor Cugnet evokes a range between 5 and 20 years, which would mean a loss of range between 1 and 4% per year. The number of allowed charge / discharge cycles  is  between 1000 and 1500.
From a pessimistic view, in 5 years my Twizy would have a range of 48 km (30 mi) and maybe 40 km (25 miles) in extreme conditions of temperature, which is compatible with my 20 km (12 mi) daily travel needs.

Regarding the number of cycles, if we take an average of 5 cycles per week, ie 250 cycles per year , the battery becomes "unusable" after 4 to 6 years.
About me, I am rather to 4 uncomplete cycles a week, ie 200 cycles per year corresponding to a life expectancy of 5 to 7 years .

How to store a lithium-ion battery to the best of his abilities ?

- Focus on short charge/discharge cycles, ie recharge little and often but do full loads from time to time.
- Avoid too frequent  fast charges (with Twizy, no problem, because no fast charge is possible).
- In hot weather, avoid charging the battery to 100 %.
- When not in use for a long  time, keep the vehicle in fresh conditions with a load of 40-50 %.
Edit 21/12/13: In this case you must remove the fuse that protects the battery (60A big fuse on the Twizy) so that no element of control or standby consumes.

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