lithium ion battery pack Britain's biggest cycle maker reveals first electric folding bike

The government has declared war on the internal combustion engine, and no new gasoline or diesel cars have been sold since 2040.
But long before that, the driver could be tempted from their car by an electric car "razed to the ground": a Brompton folding bike with a built-in bikein motor.
Brompton was born in Central America.
In his 1970 s, in a temporary workshop in an apartment overlooking the Brampton lecture hall in west London.
The emergence of a young engineer named Andrew Ritchie has drawn attention, and Brompton has now become the largest bicycle manufacturer in the UK.
By November 2016, the bike was produced at a large new factory in Greenford, north.
The Duke of Edinburgh officially opened west London.
But the company wants to encourage more people to choose two wheels.
Research has shown that many potential cyclists are intimidated by the efforts needed to solve the hills and the problems associated with sweating on their way home or social activities.
So a small team started working on an electric version of the classic Brompton.
Electric bikes are fairly common now, but generally large and bulky motors and batteries are completely unsuitable for small, relatively lightweight folding bikes.
As a result, Brompton boffins worked with engineers from Williams senior engineering (evolved from the f1 team) to develop a 250-
Watt motor around the front hub. A custom-built lithium-
Ion battery pack developed
The torque sensor is an important electronic component.
The device measures the amount of effort that cyclists put on the pedal and cuts off the motor at a predetermined point in time.
The rider needs to do some work, but when the traffic lights change, the motor takes less effort to handle the gradient and start.
Once the speed reaches 15 mph, the motor slows down completely.
Tony Wheeler, a former automotive engineer
The founder of Lonely Planet travel guide and author of bicycle books were invited to test-
Prototype of electric bike ride.
When he rode his bike gently on a quiet street in the outskirts of Greenford, he said: "I think it's pretty good.
It still folds but you don't have to work hard on the mountain.
"The basic Brompton costs about £ 900, but the electric version originally costs £ 2,595.
Potential buyers will be invited to register the production model, which is expected to start offline in early 2018. Mr Butler-
Adams said: "It needs to be under pressure and sweat from cycling.
It would be better if more people were allowed to ride bicycles and more people realized that it was a tool for walking around the city.
"It makes riding in the city a complete pleasure.