BATTERY PROTECTION POUCH, HEREIN REFERRED TO AS "BPP KIT"

POCHETTE DE PROTECTION DE BATTERIE APPELEE « BPP KIT »

Description

CA 02947538 2016-11-04
Subject of matter of the invention:
The invention consists of a protective application for cordless power tools.
It employs a flexible outer
cover as a means to shield the device from the elements, as well as preventing
accidental ejection of the
battery pack during use. A retractable safety strap is incorporated into the
protective sheath (or tool
handle) to help mitigate accidents caused by the operator losing control of
the power tool.
Here called:
Battery Protection Pouch, herein referred to as "BPP kit".
Scope of Invention:
The invention generally relates to cordless power tool applications, in
particular those employing a
removable battery-pack housing for its operation.
Background of the invention:
The purpose of developing such a device was realized through personal work-
site experience, where
many such tools are commonly utilized. Construction environments are uniquely
challenging in that they
scarcely provide the luxury of immediate access to existing formalized power
grids. The flexibility of
using portable power tools comes at the expense of a limited power supply.
Additional difficulties
include harsh work environments, where exposure to the elements can
significantly impact work
progress and efficiency. Battery efficiency suffers significantly in
conditions of extreme hot or cold and
moisture.
Work-site injuries caused by fallout are common, costly and largely avoidable.
The vast majority of
power tools manufactured today are constructed from plastics, which over time
can weaken from the
friction of frequent engagement and disengagement of the battery housing from
the unit. Replaceable
battery packs need to be secured against accidental disengagement from the
mechanical part of a
cordless tool assembly. Additionally, the incorporation of a safety strap can
significantly reduce the
chance of injury to others and damage to the operating unit and its battery
pack.
Introduction:
The primary function and design of this invention is to improve work safety
and to augment the
efficiency of battery cells by providing a necessary moisture barrier to
protect against an extreme range
of environmental and climatic elements. The battery housing itself,
traditionally constructed from a
rugged synthetic material, offers only basic shelter to the battery cell
assembly. Past inventions
concentrated their efforts on inner parts, mainly electronic improvements and
more efficient venting.
1

CA 02947538 2016-11-04
The combined battery weathering pouch (BPP device) serves following role:
1) Protecting the battery pack from accidental disengagement from the
mechanical portion of the
tool (i.e. fall out causing lethal harm to bystanders).
2) To protect the battery pack (cells) from out of tolerance low-
temperature operating conditions.
This is of particular importance in high elevation construction applications
because of the harsh
working environment. Examples include: shipyards, high-rise buildings,
communication masts or
towers, power line maintenance, general outdoor works etc.
3) Winter or off season battery storage; where its use may vary from
industrial to residential
applications.
4) Environmental benefits include: decreased recycling and disposal time, and
extending the
operating time and life span of battery cells.
The present invention provides a method to prolong battery cell life span and
duration, while at same
time combining practical remedies in overall safety enhancement for the user
and bystanders.
Other aspects associated with this invention pertain to the end user and the
proprietary battery (pack)
manufacturer. In most cases the manufacturer warranty limits the use of
battery packs to ambient room
temperature. More frequent recharging depletes the battery cell lifespan, and
thus efficiency.
With the implementation of this invention, both the end user and the battery
pack manufacturer
become beneficiaries. The BPP kit serves as a marked improvement in the
standard of safety regarding
the application of cordless power tools. In work site scenarios, a battery
pack may accidentally
disengage from the mechanical portion of the tool for a number of reasons: the
battery was improperly
installed, the guide tracks or clips have become worn or damaged, significant
vibration (impact drill),
angle and grip of device by the user in conjunction with the previously
mentioned factors.
The free-fall of a battery pack from a high elevation, regardless of its
actual size or weight can cause
serious injury or death. Accidental damage to a battery pack is not covered
under standard warranty
policies. In most cases the manufacturer's limited warranty applies to typical
but not extreme working
conditions.
Safety issue:
Presented invention decreases overall chance of accidental disengaging of a
battery pack (sliding off)
caused perhaps by not intentional movement of a tool operator or due to its
prolonged use. Wear and
tear of its guiding trucks, connecting channels becomes more imminent, as
plastic material wears faster
compare to all metal made parts and recharging cycles must be increased as the
battery becomes weak.
Overall combination of poor workmanship, poor maintenance habits and poor
workers safety training
becomes an immediate threat of harm, which varies depending on the context in
which the cordless tool
is implemented but not limited to an extreme condition of work place, confined
spaces or high elevation
works type and on.
Based on the aforementioned, the invention strives to make improvements to
protect the battery pack,
its electronic parts in conjunction with the cordless tool housing, the user
and possible bystanders. This
is achieved through the very simple and economical design of the BPP.
2

CA 02947538 2016-11-04
The invention provides flexible insulation and shock-buffering protection for
the battery pack;
effectively eliminating the potential for dangerous projectiles of debris
should the unit be dropped from
a significant height onto a hard surface. The battery protection pouch will
contain any shattered pieces
from being launched outward from the point of impact.
The following illustrations demonstrate common worksite situations where extra
caution must be
exercised in regard to safety:
Figure 1 - Typical safety technique implemented on work sites. A single strap
secures a cordless impact
drill from its handle.
õ
r
ior - r
t
#
- - _
'
Figure 2 ¨
The same cordless drill secured with a safety strap, but implementing the BPP
kit - securing against
accidental disengagement of the 36V battery pack.
..iorttc '
-Aft
Ar= = -* = ='n's
: = õ, VA:41 T
A 3
a..be
V ,
i>õ
- = = = - I
Pi*
3

CA 02947538 2016-11-04
Larger capacity battery packs such as those of the 24 volt and 36 volt
configuration weigh significantly
more than a standard cordless drill battery pack and are at a greater risk of
accidental disengagement
due to the greater stress on the locking point. A cordless battery pack may
disengage from the operating
mechanical tool for a variety of reasons such as, but not limited to:
vibration, angle of operation and loss
of control due to human error.
In Canada alone, construction safety rules prescribes working remedies to a
given work scenario, here
said: must use a safety strap fall arrest while operating a cordless tool on
higher elevation more than 10
feet. This safety rule is written in conjunction of a standard fall arrest
system implemented by an
individual workman, regardless if operating on a concrete surface, scaffold or
lifting platform.
. .7,, ' ' . ' ' - e4it*. ' '. 4 ' '=
U,"; : ''''' * r-
= . µ, ,' ',.. k' `1V6 ,
' 4'.:**,t . 7, \ '' =
=
otA
= .rif t ,4 i ' '
',..,
I' ' 'tµ
\
' .' ' = rIVT , '.- ' ip. F4
i
.. ,
7 %k.
'
, ar . - ,
40% P k
:::: .
" , I.. ,.
iikyitis- .
.
4/4
k 1 6
....r.
t= 4:'- , :'' gl. = ,, '
.
1 ,
The BPP addresses these issues and adds a preventative level of safety to
cordless tool applications.
The Velcro straps implemented into the BPP device serve as a safety feature in
order to hold the battery
pack firmly in place, preventing its accidental disengagement.
It is a common occurrence on work sites for a battery pack to disengage and
drop from the mechanical
unit due to vibration or weakened guide tracks or clipping brackets.
4

CA 02947538 2016-11-04
Figure 3 ¨ A compact cordless impact tool, secured with a fall-arrest strap
and the BPP kit.
BP; Kit ,
' z strap line
from fall ,. ',..,...., s *. i .%:. 011:-11" &
policy)
ouv slipt p
ff
ii
",--...
¨
t k' =
-*- = 'IV i 4
.k= : ,
,
,
¨^
1
,
---- / - = 'µ iip
/
-1.- it
4 , ,
f. .
*
0.
4 '41.t_ .? ooil
typical compact . ... ¨.../.,-4 \
* --"' ' / r / ' AN ' '
cordless toll ,,,, ,10/ *.,,,,,
'V, 4
L-s = I' , ,..1 .
'
- '.... ... * 4.. .
Distinct features and innovations
No previous constructions of a cordless battery pack outer shell assembly to
date have addressed safety,
performance and efficiency the way the BPP does. In general, battery cells are
protected by a custom
fitted plastic composite material. The container (battery case) is vented
through vent holes to allow the
gases that form within the cells to escape.
The presented invention serves a dual purpose. First, to secure the removable
battery pack to the
mechanical assembly of the tool, and secondly to utilize the flow of hot air
being vented out by the
electric motor during its operation to aid the battery pack in maintaining an
optimal operating
temperature range. In simple terms, heat generated inside the tool (body of
the tool; the shell) from its
operation that would otherwise be channeled out and away from the unit is
instead captured and used
to buffer battery cell temperature.
By withholding and recycling even a small amount of hot airflow the BPP
invention improves the overall
productivity of a cordless tool battery pack (particularly in conditions of
extreme cold). This feature has
not been seen or implemented in past inventions by cordless tool
manufacturers.

CA 02947538 2016-11-04
References of relevant patent applications that pertain to "battery cooling
systems"
This problem has been mentioned and addressed in US Patent nr 7733054 B2
classified under Thermal
Management Systems for Battery Pack. In regards to its early publication: US
Patent 20030027037A1
the problem of venting (out) batteries is described as following:
õ the present invention relates to battery cooling systems and, more
specifically, to systems for cooling
batteries for cordless power tools". In addition Section 0004 of that
application states the following:
"...the heat created during discharge of the batteries as well as charging of
the batteries which, in turn,
leads to increased temperatures, may have a severe effect on the life
expectancy and performance of the
batteries. In order for batteries to properly charge, the batteries must be
below a desired threshold
temperature and the differential temperature between the cells in the battery
pack should be minimized.
Likewise, if the batteries become too hot during use, battery life will be cut
short. Also, if a battery is
below a certain threshold temperature, it will be too cold to charge and must
be warmed before
charging. Thus, it is desirous to maintain batteries within a desired
temperature range for optimum
performance as well as optimum charging."
That is a fair and true statement.
However technical abbreviation of Thermal Management has other meaning:
conserving the energy.
Thermal Management by definition is implicit in the conservation of energy. In
this particular
application, this can be achieved by redirecting and reusing the hot air and
gases generated by a
cordless power tool's electric motor and its battery cells to maximize
operating temperature efficiency.
In this way the BPP kit invention enhances energy conservation.
New features compared to some previously registered invention (a specific
reference made):
It is well established that NiCad type batteries contain toxic metals, and a
common problem when
heated (eg. recharging battery cells) is that gases generated must be vented
out to prevent possible
pressure buildup inside the battery pack housing.
Therefore, specially designed venting holes are implemented (US patent
reference Nr. 7733054) to
eliminate or minimize such scenarios (volatile gas buildup).
The BPP device has been designed and constructed to withhold an excess of heat
generated within a
certain area of the cordless tool to keep the battery pack warm as long as
possible and to prevent its
rapid discharge to the outside environment. To elaborate, the design of this
invention allows for the
discharging gases generated by the unit to circulate freely around the battery
casing, and finally
escaping (at a much slower rate) without risk of causing an explosion or fire
because the BPP device is
not an air-tight constructed apparatus.
6

CA 02947538 2016-11-04
Additional considerations:
The venting ports mentioned as per patent registry references: 7733054 -
20030027037A1 here state
that by creating a direct airflow and allowing the discharge of heated gases
to escape the cordless tool
casing assembly and further throughout battery housing enables a cooling
action.
This is truly beneficial in summertime use, or in dry shop or factory
environments. However, it has been
established that the same venting holes have a negative benefit in cold, damp
climates where rainfall
and snowfall are typical. The exhaust or venting ports allowing heated gases
to be discharged from the
battery inner housing have one major disadvantage:
Through these constructed vents, moisture or condensation may penetrate the
battery pack cells
causing premature damage. If a cordless tool has been steadily exposed to rain
or snow, these venting
outlets can allow moisture to penetrate inside the battery housing,
consequently causing irreversible
damage to the cells, thus shortening the expected battery life span.
Typical venting ports (as illustrated below)
/../ ,,,,,
NNN
N, , ,
,,,.. .....
= ii " ' - - - - - ' ¨
* =, ;,,,õ:".:
=:
...00.
' , ' =.:=:== A.-.*4.1=-c- -- .,,,;,
' = 4 ' .4 " f ..',,r,! ' '=''
.,t g. ,
= . ; . 4., ,,,,,,- . - : =:,, 1 , I
fi ! ill!: : ! ii i a 0 . i,
llel4ir
. ,...õ..,.., - 1`.= 4'34 '
IP ' .= W AV a= 2 , )
* " :':' , I 1 IN ' -
....----
-
rihrffitio* 661051401124 - ,:
Illustration below - battery cell corrosion caused by excess moisture
penetration of the venting ports.
typical positioning ofhi;at .754ree' :
- ...= = radiant ports, eg, aluminium
r'''...L.,...'"?.... dates or high thermal i 1µ ' ' \
¨ Lonductivity plates, postioniong .c, c i . 4 , '',4- , ' 44,-
X' y varies, too, bottom or side ..- + N.
of the battery shell boxing
,
1,
, -. Nt T
=,,,,,,,,,,õro,-,õ14.,... =
' ' õlb.,. ' .=,-..c.05,0. õ-s;e0,04,-.0
'=,. = N, 111%, SO=cioceN ,cicio co ' 114 ' -
4
', .'= s'v *Esc.% .c.,ociaol.....õicii.,4,-,. A
1,-
\
77 0, . it= -V,4c0,04cir= - ./. - , "--'
\ = A µ-'µ .N5. Frcdl'erv;': : ....., - 2' 4' ': 1
414
.0641101te '''' ' 44'' = ' ithr 4:14<,4f.
* itg?
7

CA 02947538 2016-11-04
Solution to the matter:
Without additional weathering protection and an effective moisture barrier,
battery cells will
prematurely be exposed to corrosion. Consequently, the battery pack may become
unstable, and
impossible to be fully charged due to the reduced integrity of the battery
cells and its contact points. It is
well known fact, that moisture buildup inside battery inner box will cause
harmful reactions between
the electrodes. The BPP remedies these issues and more in a simple cost-
effective manner.
Optimum operational use and the temperature factor (science and technology
explanation):
Foreword:
It is not the inventor's position to compare, discuss or criticize a given
type of battery cell or its possible
advantage or disadvantage with regards to general cordless power tools and
their performance.
Regardless of the battery pack utilized (NiCad or NiMH or Li-ION) there is no
intention stated or
otherwise implied by the inventor to endorse the comparative advantages or
limitations of a particular
battery technology. No matter how sophisticated a battery pack can be
constructed, the fact remains:
The temperature level is a major factor in the longevity and overall
performance of a battery cell pack.
Most batteries (portable, liquid or solid) are designed to operate optimally
between 10 C and 35 C, just
like the human body. Beyond these operating parameters, performance tends to
be reduced. The
performance of most batteries (vehicles, cell-phone etc..) suffers at very low
temperatures, while there
is the possibility of freezing (condensing, shrinkage) of the electrolyte and
the overall chemical reaction
is slowed. To explain this reaction the inventor makes reference to the
Arrhenius equation formula - for
the temperature dependence of reaction rates.
The equation was proposed by Svante Arrhenius in late 19th century and showed
that for every increase
of 10 C in temperature, the chemical reaction rate doubles.
Basic chemistry suggests that the higher the temperature, the faster a given
chemical reaction will
proceed. The active ingredients of the battery cells are therefore typically
engineered to allow the
maximum operating temperature range under normal dry temperatures.
Battery operating temperature (and by extension, storage temperature) has a
major impact on the
service provision, life-span and overall operational reliability.
A simplified working example may be given on this subject:
Frustrating and stressful situations may be avoided such as attempting to
change a battery pack while
working at a high elevation (eg. a transmitting tower, or an offshore windmill
turbine installation).
Not having to change the battery of a cordless power tool due to premature
discharging can make a
significant difference in task proficiency from a time saving standpoint.
8

CA 02947538 2016-11-04
Other benefits listed:
The BPP kit helps to preserve the engraved information (serial number and
battery information) that
relates to the manufacturer's claimed warranty, which often vanishes from the
bottom side of the
battery due to extensive contact with cement flooring or common dirt and
debris accumulated on its
surface. The BPP kit may also be implemented as an off work season battery
protection storage
method. Demand for energy conservation has been gaining momentum for years and
the BPP kit is an
affordable and effective solution for industrial and domestic applications.
The BPP device presents a
desirable, long-lasting performance enhancement for cordless tool battery
applications.
Summary of the invention:
The BPP device claims:
To maximize battery cell efficiency through a slower discharge rate under low
temperature operating
conditions, and to firmly secure the battery pack housing against the
mechanical part of a cordless tool
as a means of preventing its accidental fall out or disengagement.
The independent advantages of the invention as outlined in the above
documentation is a combination
of thermal protection packing and the implementation of unobtrusive safety
features, all in one
compact, cost-effective application.
Brief description of the attached drawings and practical illustration (Fig.
land Fig. 2)
Please note the disclosure and descriptions here are intended to be
illustrative and informative as per all
essential characteristics of the BPP device. In some instances, well known raw
material such us Kevlar,
Gore-Tex, Velcro straps or thermal silicone, reflecting aluminum padding etc.-
used to construct the
BPP device have not been specifically shown or described in detail to avoid
unnecessary confusion
relating to the overall size of s cordless battery, its shape , voltage
capacity, gross weight etc.
The invention may take on many specific forms, shapes and may be constructed
from a variety of
material suited for its specific task or climate zone application.
9