Week #10: Discussion results
Further research on our ideas
Group #33
Group member:
Tianhao Han
Ximeng Sun(Susie)
Xing Cao(Star)
Zhuoran Yang
RAID

Redundant Array of Independent Disks

A storage technology that combines
multiple disk drive components into a
logical unit.

It used frequently on servers but aren't
generally necessary for personal computers.
RAID

It allows you to store the same data in
multiple paces in a balanced way to
improve overall storage performance.

Data is distributed across the drives in
one of several ways called "RAID levels”.
RAID Controller Batteries

Why we need RAID batteries?

How does a RAID battery work?

Types of RAID battery.
Why we need RAID batteries?
 It
allows the raid card to remember what
is in its buffers.
 An
UPS is not safe enough.
How does a RAID battery work?

The battery is fully discharged at first. Once the server
is powered, the battery begins a full charge cycle. On
most controllers, it takes three hours to fully charge the
battery.

The controller can be used during this time; however,
the battery is unable to meet the specified holdover
time until it is fully charged. The battery is still able to
handle brief power losses during the initial charge cycle.
How does a RAID battery work?

The battery is designed to provide a
minimum of 72 hours protection for
DIMMs up to 64 MB and 48 hours
protection for 128-MB DIMMs.
Types of RAID battery

NiMHi batteries
NiMHi batteries require that you run the battery
recondition task every six months to maintain reliability. A
battery recondition fully discharges and then recharges
the battery. When the battery needs reconditioning, the
controller reports its state as Degraded or Low Charge.
Types of RAID battery

Li-Ion batteries
The Li-Ion or lithium ion batteries are
automatically reconditioned by the
controller.These batteries do not require
that you run the battery recondition task.
Types of RAID battery

All RAID controller batteries should be
replaced every three years.
Ideas

Use fuel gauge chip, battery charge
management chip and LED to show how
long does this RAID battery can be used.

Combining solar energy to RAID battery,
so that the RAID battery can provide a
long time protection .
Kinetic Energy Recovery
System
KERS
What is KERS?

KERS is an automotive system for
recovering a moving vehicle's kinetic
energy under braking. The recovered
energy is stored in a reservoir(such as a
battery or flywheel) for later use under
acceleration.
KERS
Motor and
electrical
generator
KERS button
KERS
Motor generator unit
Battery
management
system
Two kinds of KERS
1:Store the energy to flywheel
 2:Store the energy to battery

Why Flywheel?
Can store more energy than a battery for
its weight.
 Can be charge/discharge very quickly.

Why Battery?
Cheap than flywheel.
 Flexible
 Mature technology

Why we choose second choice

Battery:
1: Can build in any shape. So we don’t
need to redesign the transmission.
2: Cheap, less money than the flywheel.
Why we use this system?

European emission standards:
2007: CO2 emission 160g/km
↓↓
2012:CO2 emission 120g/km
Seems Hybird passenger vehicle will have a
big market.
Ultra Low Power Boost Converter with
Battery Management for Energy
Harvester Applications
----------------BQ25504
Feature





Ultra Low Power With High Efficiency DC/DC
Battery Status Output
Programmable Dynamic Maximum Power Point
Tracking (MPPT)
Energy Storage
Battery Charging and Protection
Boost Converter/Charger
Applications










Energy Harvesting
Solar Charger
Thermal Electric Generator (TEG) Harvesting
Wireless Sensor Networks (WSN)
Industrial Monitoring
Environmental Monitoring
Bridge and Structural Health Monitoring (SHM)
Smart Building Controls
Portable and Wearable Health Devices
Entertainment System Remote Controls
Description
The bq25504 is the first of a new family of intelligent
integrated energy harvesting Nano-Power management
solutions that are well suited for meeting the special needs of
ultra low power applications.
 The product is specifically designed to efficiently acquire and
manage the microwatts (μW) to miliwatts (mW) of power
generated from a variety of DC sources like photovoltaic
(solar) or thermal electric generators.
 The bq25504 is the first device of its kind to implement a
highly efficient boost converter/charger targeted toward
products and systems, such as wireless sensor networks
(WSN) which have stringent power and operational demands.

Description


The design of the bq25504 starts with a DCDC boost
converter/charger that requires only microwatts of power
to begin operating.
Once started, the boost converter/charger can effectively
extract power from low voltage output harvesters such
as thermoelectric generators (TEGs) or single or dual
cell solar panels. The boost converter can be started with
VIN as low as 330 mV, and once started, can continue to
harvest energy down to VIN = 80 mV.
Description
The bq25504 also implements a programmable maximum
power point tracking sampling network to optimize the
transfer of power into the device. Sampling the VIN_DC
open circuit voltage is programmed using external resistors,
and held with an external capacitor (CREF).
 The bq25504 was designed with the flexibility to support a
variety of energy storage elements. The availability of the
sources from which harvesters extract their energy can often
be sporadic or time-varying.
 Systems will typically need some type of energy storage
element, such as a re-chargeable battery, super capacitor, or
conventional capacitor. The storage element will make
certain constant power is available when needed for the
systems. The storage element also allows the system to
handle any peak currents that can not directly come from the
input source.

Related End Equipment
Parametric
bq25504 3mm x 3mm QFN16 Package
Typical Solar Application
Circuit
Typical TEG Application
Circuit
HIGH-LEVEL FUNCTIONAL
BLOCK DIAGRAM
Wireless charging

Electromagnetic induction

Magnetic Resonant
Inductive Power Transmission


A transmitter coil L1/A receiver coil L2
An alternating current in the transmitter coil generates
a magnetic field which induces a voltage in the receiver
coil.
The efficiency of the
power transfer depneds
on the coupling(k)
The coupling is determined
by the distance between
the inductors (z) and the
relative size (D2 /D). The
coupling is further
determined by the shape of
the coils and the angle
between them (not
shown).
Efficiency of Inductive power
transmission



The values are shown as a function of the axial distance
of the coils (z/D). The parameter is the diameter of the
smaller coil D2.
The efficiency drops dramatically at larger distance (z/D
> 1) or at a large size difference of the coil (D2/D <
0.3)
A high efficiency (>90%) can be achieved at close
distance (z/D < 0.1) and for coils of similar size (D2/D =
0.5..1)
Resonant Magnetic Coupling
Magnetic coupling occurs when two objects exchange
energy through their varying or oscillating magnetic fields.
Resonant coupling occurs when the natural frequencies of
the two objects are approximately the same.
The yellow shows two
idealized resonant magnetic
coils.
The blue and red color
bands illustrate their
magnetic fields.
The coupling of their
respective magnetic fields is
indicated by the connection
of the colorbands.
Special designed magnetic
resonators “power sources
& capture”(efficiently
transfer power over large
distances)
•
•
•
•
•
High Efficiency Over Distance
Penetrates and Wraps-Around Obstacles
Safe for people and animals
From milliwatts to kilowatts
Devices that can fit into OEM products
And so on……
Disadvantage for Involving
Good products(Powermat, Witricity and so on )
 Weak background(Qualcomm, Wireless Power
Consortium(WPC), Witricity)
 No convenience enough(what we image is looking like
Wifi)
 Less room for device and increasing technology for
battery(maybe using the big capacity battery)
 More standard(at least 6) and difficult to spread
 Be replacing by other battery(Li-air battery)

Question time.
Thank you for your listening!