FIELD OF THE INVENTION
The present invention relates to solar chargers for batteries. More
particularly, the invention relates to a foldable portable and non-fragile solar charger.
The Solar Cell D.C chargers are based on single crystal or multi crystalline
silicon solar cells. These chargers use the full size (125 * 125 sq. mm) solar cells having
higher wattage and uses. Aluminum frames. The higher wattage Solar Cell Chargers are
available in the capacity of 70 Watt and 150 Watt, which are fragile and are not foldable.
In the prior art solar modules, the silicon solar cells are integrated and laminated between
a glass and Tedlar sheet using EVA sheets as bonding material. The structure is heavy and
fragile due to thick glass sheets and these glass structures are only suitable for fixed
mountings.
Due to the higher weight, fragile nature, and folding-incapabahty of the
chargers, they are not easily transportable in particular to remote locations. For the lower
wattage modules one can use a DC-DC converter for charging 12 Volt batteries.

US Patent No.2007/0108943 Ai describes a solar charger with DC-DC converter
This type of chargers waste power in DC-DC conversion.
Thus, Foldable Non Breakable Solar Chargers for charging the batteries
are not yet prevalent and/or disclosed.
The documents CN 2563751 and WO 200477576 are close prior arts. In
CN 2563751, the portable energy charger, it and may carry on the modeling
yard lumber that including several interconnections "M" shape opens to fold,
several solar cell board, the connecting lead and belt plug's derivation wire, the
small sucker and outer layer two concave plastic films, its characteristic lies in:
And may carry on the plastic film that in several interconnections "M" shape
opens to fold (1) same inlays the same quantity at the same time the solar cell
board (3), various solar cell boards among (3) (6) by the wire meet continually,
are composed the solar energy battery, and (5) draws out with the belt plug's
wire, the solar cell board (3) side on is loaded with the small sucker (4), after
opening folds the plastic film outer layer's two concave plastic films (2) to be
possible the solar energy battery to put in the box.
WO 200477576 discloses a flexible solar panel which is preferably made
of flexible photovoltaic cells, such as for example amorphous silicon solar cells,
cadmium telluride solar cells, copper indium diselenide solar cells or organic
dye, deposited on a very thin and flexible substrate such as for instance a film
of polyimide, polyethylene naphtalate. In a variant embodiment, the flexible
solar panel 2 is made of conductive polymer layers. In order to improve the
solar panel's mechanical resistance and to protect the solar cells from
damages, it is preferably further laminated in a thin transparent flexible film.

In Patent no. CN-2563751, the solar panel and the plastic plates are
different components. In present product the module is fabricated on the
plastic plates itself. The front face of the solar panel is made of high quality
polycarbonate sheet which provide nonbreakability to the solar cells without
reducing their power conversing efficiency. The foldable edge is also an
integrated part of the module in present case, while in CN-2563751, the solar
panels are inserted in a M shaped plastic casing. Therefore, the present
product is less fragile and more cost effective due to all plastics than the
module of CN-2563751. (2) The product described in W0-200477576 is based
on thin films and totally different than the present invention. Thin films are
more prone to degradation in outdoor conditions. Product of the present
invention is based on stable crystalline silicon solar cells and will be a more
reliable product.
OBJECTS OF THE INVENTON
It is therefore an object of the invention to propose a foldable portable
and non-fragile solar charger which is light-weighted.
Another object of the invention is to propose a foldable portable and
non-fragile solar charger which enables easy transportation to remote location.
Yet another object of the invention is to propose a foldable portable and
non-fragile solar charger which adapts cut-pieces of solar cells making the
charger cost effective.
A further object of the invention is to propose a foldable portable and
non-fragile solar charger which eliminates the use of glass component in the
structure of the module

A still further object of the invention is to propose a foldable portable and non-
fragile solar charger which eliminates the requirement of a voltage charger.
SUMMARY OF THE INVENTION
According to the invention there is provided a Foldable portable and non-
fragile solar charger. The Foldable Charger can be folded like a bag and being low weight
can be taken to remote places comfortably to charge the batteries at remote places where
conventional power is not available. Also, the cut pieces of solar cells can be used to give
required power for charging the batteries of lights and the communication systems of the
Personnel working in remote and border areas. The charger is suitable to charge a 12 Volt
Lead Acid Battery.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 - shows a foldable portable and non-fragile solar charger according to the
invention.
Figure 2 - shows the solar charger of figure 1 in packed condition in a packaging device.

DETAIL DESCRIPTION OF THE INVENTION
The development of a non-breakable, foldable module shall meet this
requirement of Defence Personnel and their requirement for tent lights and float charging
of the battries can be met with about 24 watt module. Therefore a 12 V, 24-Watt
crystalline silicon foldable non-breakable module has been developed for their application.
After examining the properties of various types of plastic sheets like acrylic
etc., transparent polycarbonate (polyglass) sheets have been identified for the replacement
of the front glass in the module. Polycarbonate (polyglass) sheets have light transitivity
equivalent to the glass sheets and are quite stable under sunlight.
To make a known 70-watt module suitable to charge a 12-volt battery, 36
cells of crystalline silicon of size 125mmxl25mm are connected in series. To make a
module if 24 watt and suitable to charge a 12-volt battery, same number i.e. 36 cells are
connected in series but the size of each cell is selected to be about l/3rd

of 125mmx 125mm cell. These 36 cells have been arranged in three segments of 12 cells
each, to get a smaller size module after folding the segments onto one another. The
performance of the module has been measured on a sun simulator. The charger can collect
85 to 100 WH of energy per day.
The laying of the crystalline silicon (CSC) cells is performed as shown in
figure 1. The foldable edges (FEi, FE2) are the continuous stack of EVA and Tedlar, which
is quite flexible and strong. The foldabihty and reliability of the edges (FEi # FE2) has been
checked by repeating the folding unfolding action on the edges for 1000 times.
The module (1) is packaged in a bag (2) of Leather. Tetron, Mattie,
Parachute cloth etc. such that the front aperture (not shown) is left open so that the
sunlight is not blocked from falling on the solar cells. A provision for keeping the
connecting lead (when the charger is not in use) in a pocket (3) of the bag (2) is also
provided.
The bag (2) for packing the module (1) is shown in figure 2. The bag (2) can
be folded when not in use and can be carred from one place to another place easily. A
handle (4) for easy carrying the bag (2) is also provided.

WE CLAIM
1. A foldable portable and non-fragile Solar charger for charging batteries of lights
and communication systems in particular at remote locations comprising:
- a main module having at least 36-cells constituting of cut-pieces of
crystalline silicon, the cells are arranged into segments to form at least
three mini-modules, each mini-module comprising 12-cells, the cells being
connected in series; and
- transparent polycarbonate sheets and tedler sheets to form a housing in
which the mini modules being integrated and laminated using EVA sheets
as the bonding material, characterized in that each of the mini modules is
folded and interposed onto one another to form the main module.
2. The solar charger as claimed in claim 1, wherein each of the cells has a size
about "125 mm * 43 sq. mm".

ABSTRACT

FOLDABLE NON BREAKABLE SOLAR CHARGER
A foldable portable and non-fragile Solar charger for charging batteries
of lights and communication systems in particular at remote locations comprising a
main module having at least 36-cells constituting of cut-pieces of crystalline silicon.
The cells are arranged into segments to form at least three mini-modules, each
mini-module comprising 12 - cells, the cells being connected in series. Mini modules
being integrated in transparent polycarbonate sheets and tedler sheets forming a
housing and laminated using EVA sheets as the bonding material when each of the
minimodules is folded and interposed onto one another to form the main module.