Transcript Battery Analysing Presentation

BHG Power Storage Solutions
(Pty) Ltd
Presented by:
VISION STATEMENT
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To help South African consumers reduce their energy
consumption and dependence on carbon based fossil
fuels.
To become a market leader in the design and
implementation of sustainable energy saving
solutions.
To educate consumers on the benefits of using solar
water heating, heat pumps, water harvesting and
solar PV systems.
To extend the life of batteries to double their lifespan
Nollie Moorcroft
Tel No:
011 827 8704
Mobile No: 082 454 2817
Fax No:
086 675 0986
Email:
[email protected]
Web: www.bhgpower.co.za
Index
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Front Line Battery Monitoring
Battery Measurement
Reasons for Battery Failure
Battery Chemical and Electrical
Properties Measurement
• Software
• Overall Benefits
COMPANY INFRASTRUCTURE
 Director and Management Profile
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Nollie Moorcroft – Managing Director – General Management
Rodwell Kahondo –Director – Sales & Production Manager
Charlene Joubert – Personal Assistant
Cora Moorcroft – Admin & Office Administrator
Frik Swanepoel – Stock Controller
Blessings Magombo – Workshop Manager
PDI Status
 51% Director – Rodwell Kahondo
 49% Director – Nollie Moorcroft
BATTERY MEASUREMENT
• Voltage
• Impedance
• Battery voltage and impedance measurement is not enough as they are
only gross electrical indicators of a battery function and provide only
limited information about battery health
• This measurement are less than 100% reliable in detecting batteries that
are near failure, therefore increases the cost and risk of battery ownership
Reasons for Battery Failure
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Corrosion on positive plate
Sulphation
Temperature
Over charging / Dry out
Over discharging
Manufacturer defects
Indication of Battery Health
• Battery sulphation and dry out are chemical properties of a battery and are
precise, leading indicators of battery health
• They provide essential information about when a battery will fail
• More importantly they show when and how to apply corrective action
when caring for batteries and extending battery life
Battery Chemical and Electrical Properties
Measurement
• The EC1000 are the only Electro Chemical Battery analyser that measures a
four electro-chemical parameters (SDVI) of batteries in a single
measurement
• The EC1000 uses CELScan Technology
• This is a patented broadband swept frequency response analysis
technique that accurately measures the electro-chemical status found in
batteries
Technology
• Over the next six months, impedance trends indicated improvements in health,
not only for the most affected cells but for almost every cell in the string. In
contrast, some cells within a string that received no corrective action showed
progressive deterioration.
• Effective management of a battery installation requires timely information about
the condition of each battery unit (cell or mono-block) within the installation.
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To satisfy this requirement, EC1000 and EC2000 was developed.
• It is a hand-held Analyzers, which measure electrochemical impedance
characteristics of a battery over a range of AC frequencies
Technology
• The measurements are processed by BHG Power Storage Solution algorithms to
provide information not only about which battery units are approaching failure
but also about the nature of those failures.
• All cells are not created equal and this fact has major consequences for the
reliability of batteries. In particular, the useful life of a battery or string cannot be
projected simply on the basis of typical cell data because interactions among the
cells during operation will inevitably shorten the life of all of them.
• For the same reason, no single set of test results can reveal cells that are aging
abnormally. Only by analyzing trends in test results over a period of months or
years is it possible to identify components (cells, monoblocs or interconnections)
that may require attention.
Technology
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Cell performance charts published by battery suppliers are usually presented as “typical” and
the user is cautioned that practical results may differ greatly, depending on operating
conditions and other factors.
One factor rarely addressed by the suppliers is the intrinsic variability of battery cells. At best,
the useful life of a multi-cell battery (or battery string) can never exceed that of its weakest
cell and actual battery life can be even shorter.
Strong cells wear out more rapidly because they must work harder to compensate for weaker
cells, while weak cells get overstressed with each charge and discharge cycle, degrading them
even faster.
Furthermore ,the difference between published and actual life expectancy increases with the
spread in individual cell characteristics.
Regularly monitoring the extent of this spread provides vital information about the health of
a battery string.
On the other hand, an operating plan that relies primarily on “typical” life curves will almost
certainly lead to premature (and potentially catastrophic) system failures.
Technology
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According to IEEE (The Institute of Electrical and Electronics Engineers), the only sure way to
assess the health of a multi-cell battery is to perform regular capacity tests on every cell.
However, because it is rarely feasible to perform capacity tests more often than once every
1-5 years, IEEE recognizes the value of alternative inspection methods that can be performed
at shorter intervals, stating in part that:
Internal ohmic measurements can be used to evaluate the electrochemical
characteristics of battery cells.
They may provide possible indications of battery cell problems and may identify those
cells having internal degradation.
Ohmic measurements can be used as a trending tool to identify cells that may
require further evaluation.
When significant changes from the baseline occur, capacity testing should be used
to verify whether identified cells are in fact defective.
Software
• Battery test is store , analysed and automatically formatted into a variety of
presentations-ready reports using IBMS(Intelligent Battery Management System)
• With IBMS the EC1000 and EC2000 it stays up to date with the latest , new
measurement performance features and capabilities that can be downloaded from
the WEB
• The EC1000 and EC2000 automatically calculates the proper battery measurements
limits(Alarms)
• It provides automatic pass and fail warning , visual and audible feedback as to the
process in measuring each battery in the string
• It stores up to 50,000 battery test data including string configurations and other site
details
• All data can be downloaded to your computer using IBMS
Test Results Fig 3
Test Results
• The yellow and red lines in these charts represent “Warning” and “Fail” levels
that were chosen by the operator. It is immediately apparent from these
charts that, while most of the cells were operating within acceptable limits,
there were several cells that required attention. Note that none of the cells
in this string were flagged as abnormal by either of the conventional
measurements of float voltage or (single-frequency) impedance. The only
indicator that detected abnormal cells in this string was the relative sulfation
level.
Test Results Fig 4
Test Results Fig 5
Test Results Fig 6
Test Results
• Based on the abnormalities apparent from Figures 3 and 4, a program of regular
equalization procedures was recommended. Data collected on the same cells six
months later are shown in Figures 5
• Comparison of Figures 4 and 5 shows that equalization successfully lowered the
sulfation
• Levels of all three abnormal cells. To see how these cells fared over time, we
generated “cell history” bar charts of the individual sulfation parameters over
a six-month period. Results for four of the cells highlighted above appear in
Figure 6.
Test Results Fig 7
Test Results Fig 8
Test Result Fig 9
Summary
• These results clearly demonstrate that virtually all cells in String A derived
significant benefit from the de-sulphation procedure.
• By de-sulphating on regular intervals will improve battery capacity and life
expectancy
• However, as shown in Figures 8-9, very different trends were observed on a string
of 120 cells that did not receive de-sulphation procedure.
How Frequent
• Bi-annually.
Overall Benefit
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Identify bad battery before failure
Reduce battery replacement cost
Reduce labour cost by not over testing batteries
Reduce or eliminates the need to measure specific gravity
Reduce the need of load testing
Reduce lost revenue by avoiding system shut down due to battery failures
Reduce risk to capital and personnel
BHG Power Storage Solutions (Pty) Ltd
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Reg No:
Vat No:
Tel No:
Mobile No:
Fax No:
Email:
Web:
2014/043541/07
4090265234
011 827 8704
082 454 2817
086 675 0986
[email protected]
www.bhgpower.co.za