Specifications

US 2011/0181242 A1
MULTI-CHEMISTRY BATTERY CHARGING
SYSTEM AND METHOD OF IDENTIFYING
AND IMPROVED CHARGING TECHNIQUE
FOR PRIMARY AND SECONDARY
DRY-CELL BATTERIES
FIELD OF THE INVENTION
[0001] This invention relates to charging of batteries. It
relates to primary batteries Which are generally considered
non-rechargeable and secondary rechargeable batteries. lt
particularly relates to the multitude of different batteries for a
multitude of different electric and electronic devices.
BACKGROUND
[0002] As society is becoming increasingly mobile, We see
the rapid adoption of mobile phones, laptop computers, palm
devices, personal stereos, remote controllers and as any par
ent knoWs, a huge array of electronic toys. Batteries are the
poWer source of necessity for these devices Which have
become an everyday part of life Whether at Work, at home and
at play.
[0003] The prior art illustrates a strong lack of options
delivering ef?ciency and effectiveness and fails to provide a
convenient and cost effective solution. Currently, the con
sumer is expected to merely purchase a neW battery every
time a battery goes out.
[0004] Many people take up rechargeable batteries so that
the batteries can be recharged and reused over and over again.
The disadvantages of rechargeable batteries are that they cost
much more than primary batteries and replacing the Whole
house With a rechargeable system Would be out of the ques
tion for most people. Further, rechargeable batteries lose their
effectiveness and, in particular, their period of time ‘in use’
decreases and they are therefore required to be charged more
frequently over time.
[0005] In addition, rechargeable batteries are rendered
unsuitable for many electronic applications as rechargeable
batteries have a very fast self discharge rate compared to
primary alkaline batteries.
[0006] Further, a recharging battery requires a complicated
battery charger Which adds further cost to the consumer and
can be quite dif?cult or complicated to operate. In addition,
When the battery goes ?at recharging requires an external
poWer source, such as a poWer outlet. When the battery is not
charged effectively, it is cumbersome and impractical to
locate a poWer source When mobile or in transit.
[0007] There is a complex number and variety of battery
types available on the market that includes rechargeable
nickel cadmium and nickel metal hydride batteries as Well as
primary carbon Zinc, alkaline and rechargeable alkaline bat
teries. Adding further to the complexity and confusion of
rechargeable and non-rechargeable batteries are neW alkaline
variants called Titanium and long lasting advanced formula
batteries and so forth that truly making recharging batteries a
mine ?eld for many people.
[0008] For one reason or the other, primary alkaline batter
ies still remain a part of our ZO everyday life. They are readily
available everyWhere and their toxic Wastes continue to
threaten land?lls and Waterways. Many attempts have been
made to come up With systems that can recharge primary
alkaline as Well as rechargeable batteries to help save money
and the environment. Up until noW, all recharger systems
available are at their infancy stage and suffer from a Wide
Jul. 28, 2011
range of short comings that made them unreliable and/or
unsafe to use. Clearly there is a need to come up With a
multi-chemistry battery recharging system that can overcome
most if not all of the short-comings knoWn that are reliable
and safe for consumer use.
[0009] Several prior art disclosures suggest different means
for discriminating betWeen primary and secondary batteries.
One method disclosed the measurement and use of internal
battery resistances to distinguish betWeen primary alkaline
and secondary NiCd batteries as outlined in US. Pat. No.
5,600,224. HoWever this method is not reliable as consumer
batteries are becoming complicated in recent time With more
battery types added to the list such as the addition of the neW
breed of advanced formula alkaline batteries With very loW
internal resistances and the environmentally, more friendlier,
NiMH and rechargeable alkaline batteries Which make the
distinguishing line not so apparent. Furthermore as batteries
age, their internal resistances become higher and the values
overlap one another Which make this distinguishing task
using internal resistances even more unreliable.
[0010] The most commonly seen method employed in
chargers, charge only batteries having a certain predeter
mined feature. These hoWever are not entirely satisfactory
from the combined standpoints of safety, ease of use and more
importantly these do not meet the criteria to be considered as
universal recharging system that accepts most chemistry
types of batteries.
[0011] Also, commonly seen approaches use mechanical or
electronic sWitch selections as a means to distinguish the tWo
battery types and thereafter apply a loW charge current to
primary alkaline batteries and moderate charge current to
rechargeable batteries. These systems rely on the users to
make complicated and often confusing selections that could
lead to Wrong operating settings either through plain human
errors or technical ignorance. The consequences of such
errors Would cause adverse battery leakage, damage to bat
teries and chargers and, in Worst cases, lead to dangerous
battery explosions. Another short coming using this approach
is that the system cannot charge different mix of batteries
simultaneously. This type of chargers usually only can charge
single battery type at a time.
[0012] Further, in practice there is the use of a common loW
charge current safely recharging both types of batteries so
they can co-exist Within a single charging system. This is the
closest system that can overcome many problems encoun
tered previously and is safe to use. HoWever there are short
comings With this technique as Well as it taking at least 15
hours or more to charge up primary alkaline and rechargeable
batteries. Even With the lengthy charge time, this system still
cannot fully charge up many high capacity rechargeable
NiMH batteries.
[0013] So there is a need to come up With a more ef?cient
and effective method to automatically detect and distinguish
primary and secondary dry-cell batteries Without any involve
ment of the error-prone user interaction described above.
There is also a further need for a faster and improved charging
method that can properly recharge most different battery
types Within a single system.
[0014] The present invention attempts to overcome or at
least ameliorate one or more of the problems of the prior art
and to achieve or at least progress toWards achieving one or
more of the folloWing objects of the invention.