Prepared for 7 x 24 Exchange
What do you know about EnerSys?
• World’s largest Industrial battery company
• Headquartered in Reading, Pennsylvania USA
• Annual revenue in excess of $2.0 Billion; over
9000 Employees worldwide
• Manufactures and distributes industrial batteries
in three markets
– Reserve Power – Motive Power –
Aerospace & Defense
• Broadest product portfolio in industry
• Nationwide Service Group
Product Applications Reserve Power
Telecom – Wireline
Telecom - Wireless
Extended Run time
Wind & Solar
UPS
Railroad Crossing Backup
Purpose of Batteries
• Once AC power is lost, batteries pick
up the load until the generator starts or
until power is regained
• Batteries provide power for both AC
and DC equipment during outages
• Benefits of using batteries
– Immediate response (compared to
generator)
– Do not require fuel source to be
replenished
– Noiseless (no muffler)
– Only emissions are Oxygen & Hydrogen –
no Carbon or Nitrous emissions
Lead acid battery components
• Lead-acid battery consists of two
dissimilar metals in acid solution
– Positive plate – PbO2 (black or
dark chocolate brown when
healthy)
– Negative plate – Pb (light gray or
gray)
– Acid – H2SO4 (clear – water and
sulfuric acid mixture)
– Separator (keeps positive and
negative plates from touching)
– Jar/Cover (you have choices)
Lead acid battery construction
Typical Lead Acid Plate
Primary
failure of a
lead acid
battery is
due to Grid
Corrosion
Grid
8
Pasted Plate
Pros & Cons of VRLA
Pros
Cons
Low maintenance technology
Relatively low energy density (heavy)
Long float life, specially pure lead
Cannot be stored in discharged state
for too long
Quick charge and discharge
capability
Lower cycle life than NiCd cells
Charging and orientation flexibility
Thermal runaway possible with
excessive overcharge or improper
thermal management
Wide operating temperature (-65ºC
to +80ºC)
More sensitive to high temperature
than flooded lead acid cells
No “memory” effect
State of charge easily measured
(OCV)
Low cost of ownership
VRLA metallurgy
• Pure lead
– Grid metallurgy used when VRLA technology was
introduced in the 1970s in a cylindrical format
• Lead calcium
– Introduced mainly to overcome manufacturing issues
with pure lead
• “Pure” lead-tin
– Combines strengths of pure lead and lead calcium
technologies while minimizing their weaknesses
Conventional Lead Calcium Battery Grids
Use of a hardening alloy:
Provides stiffness and strength
for handling and manufacturing
Grid is Cast
Costs less to manufacture
Accelerates grid corrosion
Accelerates self-discharge
Requires thicker plates for longevity
12
The Difference can be see in the Grain Structure
Conventional Pb-Ca-Sn “Book Mold” Cast
Grid
Prone to growth and corrosion at grain boundaries
Must be 3 to 4 times thicker than Pb-Sn or Pb grids for same
life. High internal losses = short storage life
Cold Rolled Pb Strip
High purity lead (no hardening agents or
tin) Cold rolling process produces finest
grain structure. Highest resistance to
anodic corrosion.
High purity grids and electrolyte for long
storage life
13
Lead Acid Battery Failure Mode
Corrosion
the oxidation of the battery grid
▼Oxidation of the lead grid
causes plate growth and
eventually destroys the grid
14
Typical VRLA Batteries
Positive grid alloy is Pb-Ca-Sn
Corrosion at the grain
boundaries leads to:
• Grid corrosion
• Grid growth
• Reduction in current carrying capacity
• Loss of contact between grid and active material
EW/Thin Plate/10/02
15
TPPL Pure Lead Grid
Pure Lead Crystalography
The very fine grain structure makes
the grid far more resistant to corrosion
• Pure lead grids with the same
design life can be much thinner
than Pb-Ca grids
EW/Thin Plate/10/02
16
High Purity Materials
Virgin Lead
Oxide
Virgin Lead
Medical Grade
Acid
EW/Thin Plate/10/02
17
High Purity Materials
High purity materials are more expensive….
but the advantages outweigh the extra cost!!!
The advantages of high purity materials are:
• Low rate of self discharge
= Long Shelf Life
• Low float charge current
• Low rate of grid corrosion
= Long Service Life
• Low gassing rate
• Thinner positive grids
= High Energy Density
High Performance
EW/Thin Plate/10/02
18
TPPL Technology
VRLA Grid Thickness
Thick vs Thin
Cells are:
Cells are:
• Large
• Smaller
• Heavy
• Lighter
Grids are:
Pb-Ca
SBS
• Prone to
corrosion
and growth
Grids are:
• Resistant to
corrosion and
growth
Equivalent Float Life Products
EW/Thin Plate/10/02
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Pure Lead vs Lead Calcium Positive Grids
Positive Grid Corrosion
Battery service life is limited by the positive grid which slowly corrodes
The rate and the nature of corrosion is effected by float/charging current,
grid material and design
Lead Calcium Tin (Pb-Ca-Sn)
Pure Lead (Pb)
Life Battery
21
Another Major Difference for TPPL
Typical Lead Calcium – Grid
is Cast
TPPL - Grid is Cold Rolled
or Chill Cast and Punched
2 V 2.5 AH
D CELL
SEALED-LEAD
RECHARGEABLE
BATTERY
22
TPPL Models
Thin grid technology requires
special manufacturing techniques
A thin strip of lead is fed into a
perforating machine, which
punches out the holes that will
contain the paste pellets
Warrensburg, SBS J production
EW/Thin Plate/10/02
23
TPPL Processing
The perforated strip is fed
through a pasting machine
A thin layer of paper applied to
each side of the pasted plate to
retain the paste in the grid
The strip is then cut into plates
Because the grid is so soft the
plates are easily damaged and
must be handled carefully
Warrensburg, SBS J production
EW/Thin Plate/10/02
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Why pure lead-tin VRLA?
Feature
Low internal
resistance
High purity
system
High
compression
Benefit
• Great high rate discharge capability (25C or more)
• Quick charge capability (100% capacity in 30 min.)
• Good discharge capability even at –20ºC
• Low self-discharge (2 yrs. shelf life at 25ºC)
• Longest float life among VRLA batteries (10+ years at
25ºC)
• Allows higher cyclability (1,300 JIS cycles)
• Higher resistance to vibration
High temperature
• Widest operating temperature range (-65ºC to +80ºC)
capability
Small amount of
tin
High vent
pressure
• Excellent overdischarge recovery capability
• Allows charging flexibility (CC, CV or combination)
• Accepts very aggressive charging
• Can be used in space (only VRLA acceptable to NASA)
Pure lead-tin vs. lead calcium VRLA
Feature
Pure lead-tin
(Genesis XE)
Lead calcium
(Genesis NP)
Calendar life @ 25ºC
12+ yrs. for XE
3 to 6 yrs.
1300
625
-40ºC to 80ºC for XE with jacket
-20ºC to 60ºC
Cycle life
Temperature range
Charging @ 25ºC
Quick charge
capability
Shelf life @ 25ºC
Capacity @ -20ºC (%
of 10-hr rate)
Float: 2.25-2.30 VPC; no CL
Cyclic: 2.40-2.50 VPC; no CL
Float: 2.25-2.30 VPC; no
CL
Cyclic: 2.40-2.50 VPC;
0.25C CL
100% SOC in < 30 min.
Limited by current limit
(CL)
Recharge every 24 months
Recharge every 6 months
42% @ 15 min. rate
70% @ 1-hr. rate
4% @ 15 min. rate
38% @ 1-hr. rate
Higher Energy Density
Bookmold casting requires
inherent grid strength - thick
with added hardeners
Automation of plate manufacture
allows processing of thin Pb°
grid
Result: 2 - 4 mm Thick
Result : 1mm Thin
Means the
difference
between a
155AH lead
calcium to
a 170Ah
Pure Lead
Thin = Greater Surface Area = More Power
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Recombination Efficiency
Low float current and high efficiency recombination means there
is virtually no gas emission under normal operating conditions
FLOAT CURRENT & RECOMBINATION EFFICIENCY
SBSC11
INITIAL WEIGHT (Kg)
OCV
CHARGE 2.27V/CELL : 168H
Ah IN
STABILISED FLOAT CURRENT (mA)
WEIGHT AFTER CHARGE
% RECOMBINATION
MONOBLOC 1 MONOBLOC 2
26.532
26.44
13.123
13.108
3.6
20
26.529
99.6
3.53
20
26.438
99.7
EW/Thin Plate/10/02
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SBS Technology
SBSC11 GAS EVOLUTION TESTS AT ELEVATED TEMPERATURE
TEMPERATURE FLOAT VOLTAGE (V) FLOAT I
40 C
2.45Vpc
N/A
50 C
2.45Vpc
610mA
65 C
2.45Vpc
900mA
GAS EVOLVED
0.580 LITRES/HOUR
0.880 LITRES/HOUR
2.020 LITRES/HOUR
TEMPERATURE FLOAT VOLTAGE (V) FLOAT I
40 C
2.375 Vpc
250mA
50 C
2.375 Vpc
450mA
65 C
2.375 Vpc
560mA
GAS EVOLVED
0.111 LITRES/HOUR
0.190 LITRES/HOUR
0.45 LITRES/HOUR
TEMPERATURE FLOAT VOLTAGE (V) FLOAT I
40 C
2.27Vpc
40mA
50 C
2.27Vpc
80mA
65 C
2.27Vpc
270mA
GAS EVOLVED
0.00 LITRES/HOUR
0.00 LITRES/HOUR
0.00 LITRES/HOUR
At 40C & 2.45Vpc data file corrupted so no float current value recorded
At 20C & 2.27Vpc float current ranged betw een 10 - 20mA
EW/Thin Plate/10/02
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Long Service Life
TPPL typical service life expectancy to 80% of rated capacity
MONTHS/YEAR
1
2
3
4
5
6
7
8
9
10
11
12
TEMPERATURE DEGREES CELSIUS
20C
25C
30C
35C
40C
15
14.6
14.2
13.8
13.4
15
14.2
13.4
12.6
11.9
15
13.8
12.6
11.6
10.6
15
13.4
11.9
10.6
9.5
15
13
11.3
9.7
8.4
15
12.6
10.6
8.9
7.5
15
12.3
10
8.2
6.7
15
11.9
9.5
7.5
6
15
11.6
8.9
6.9
5.3
15
11.3
8.4
6.3
4.7
15
10.9
8
5.8
4.2
15
10.6
7.5
5.3
3.8
45C
13
11.3
9.7
8.4
7.3
6.3
5.5
4.7
4.1
3.6
3.1
2.7
50C
12.6
10.6
8.9
7.5
6.3
5.3
4.5
3.8
3.2
2.7
2.2
1.9
55C
12.3
10
8.2
6.7
5.5
4.5
3.7
3
2.5
2
1.6
1.3
EW/Thin Plate/10/02
30
Quick charging lead-tin VRLA
Capacity
returned
Charge current, amps
0.8C10
1.6C10
3.1C10
60%
44 min.
20 min.
10 min.
80%
57 min.
28 min.
14 min.
100%
90 min.
50 min.
30 min.
C10 = amp-hour capacity at the 10-hour rate; 0.8C10 = 80A for a 100Ah battery
Cycle life comparison
Thermal runaway comparison
3X Increased Shelf Life
SBS Self Discharge Characteristics
OPEN CIRCUIT VOLTAGE/STATE OF CHARGE DECAY AS A FUNCTION OF TEMPERATURE
Open
Circuit
Voltage
per Cell
2.17
100
2.16
96
2.15
91
2.14
87
2.13
83
2.12
79
2.11
74
+40°C
+25°C
+30°C
+20°C
+10°C
2.10
70
0
6
12
18
24
30
36
Months
35
42
48
Approx
% state
of
charge
Up to 18 months of
storage vs. 6
months for lead
calcium.
Stop installing dead
batteries when
deployments take
longer than
expected
XE Battery Features
• 12V pure lead-tin VRLA AGM battery
• UL94 V-0 flame retardant case and cover
• Rugged construction (optional metal jacket
available, except for XE60 and XE95)
– -40ºC to 80ºC (-40°F to 176°F) with metal jacket
• Approved for shipping as non-hazardous,
non-spillable
Batteries for Flywheels
•
•
•
•
Advanced lead technology TPPL (XE)
Battery cabinets sized for <20 second loads
480V strings
600kW for 30 Seconds
– More Power and Run Time
Flywheel – TPPL Comparison
• Lower operating costs
–
–
–
–
250W float charge for flywheel
25W float charge for battery
Flywheel Uses 1,971 KW Annually
Flywheel Extra 1,944 lbs CO2 Annually
• Capital costs
– $30k for 750kW batteries
– $200k for 750kW flywheel
– 15% Cost (Initial) 30% Life (2X)
• 10 year life expectancy
• Solutions based approach
Where is pure lead-tin used?
• Anywhere a conventional lead calcium AGM
is used plus where customer is looking for:
–
–
–
–
–
–
Quick charge capability
Longer float life than conventional AGM
Longer cycle life than conventional AGM
Wide operating temperature range
Long shelf life
High rate discharge capability in a smaller
package
– High rate discharge & excellent cycle life in the
same battery
Warrensburg, Missouri Facility
 360,000 sq. ft.
 33 acres
 330+ employees
 ~30,000 Batts./day
Automated Line
 First battery plant in the world to be certified as
ISO 14001Environmental Management System
 ISO 9001 Certified Quality Management System
 1995-1997 Gold Pretreatment Award Missouri Water
Environmental Association
 1997 Industrial Water Quality Achievement Award
 FAA Certified Production Approval Holder (PAH/PMA)
 Approved Supplier to the Military
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Recycling
•EnerSys provides a complete range of recycling support services. With logistics
recovery you can contact us to arrange a drop off time, or to have us pick up your
batteries.
•EnerSys follows fully compliant processing and batteries are only sent to lead
smelters operating under Part B hazardous waste facility permits.
•EnerSys accepts all lead acid batteries. EnerSys exceeds state and federal
requirements by giving you complete recycling documentation, including Recycling
Certificates.
•“Its good for business and good for the environment”
Thank you !