William R. Bennett and Richard S. Baldwin

Glenn Research Center, Cleveland, Ohio

Experimental Lithium-Ion Battery Developed for 

Demonstration at the 2007 NASA Desert Research 

and Technology Studies (D-RATS) Program

NASA/TM—2010-216906

November 2010
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William R. Bennett and Richard S. Baldwin

Glenn Research Center, Cleveland, Ohio

Experimental Lithium-Ion Battery Developed for 

Demonstration at the 2007 NASA Desert Research 

and Technology Studies (D-RATS) Program

NASA/TM—2010-216906

November 2010

National Aeronautics and

Space Administration

Glenn Research Center

Cleveland, Ohio 44135
Acknowledgments

 Acknowledgements are given to the following persons for their contributions to this task:

 NASA Headquarters NASA Johnson Space Center Jet Propulsion Laboratory 

Chris Moore (sponsor) Craig Bernard Marshall Smart 

 Edward Ehlers Kumar Bugga

 Kevin Groneman

 NASA Glenn Research Center Judith Jeevarajan

 Gary Horsham Joseph Kosmo

 Jerri Ling Barbara Romig

 Dave Yendriga Nathan Smith

 Steve Wells 

 

Available from

NASA Center for Aerospace Information

7115 Standard Drive

Hanover, MD 21076–1320

National Technical Information Service

5301 Shawnee Road

Alexandria, VA 22312

Available electronically at http://gltrs.grc.nasa.gov

Trade names and trademarks are used in this report for identifi cation 

only. Their usage does not constitute an offi cial endorsement, 

either expressed or implied, by the National Aeronautics and 

Space Administration.

Level of Review: This material has been technically reviewed by technical management. 
NASA/TM—2010-216906 1 

Experimental Lithium-Ion Battery Developed for Demonstration at 

the 2007 NASA Desert Research and Technology Studies 

(D-RATS) Program 

William R. Bennett and Richard S. Baldwin 

National Aeronautics and Space Administration 

Glenn Research Center 

Cleveland, Ohio 44135 

Abstract 

The NASA Glenn Research Center (GRC) Electrochemistry 

Branch designed and built five lithium-ion battery packs for 

demonstration in spacesuit simulators as a part of the 2007 

Desert Research and Technology Studies (D-RATS) activity at 

Cinder Lake, Arizona. The experimental batteries incorporated 

advanced, NASA-developed electrolytes and included internal 

protection against over-current, over-discharge and overtemperature. 

The 500-g experimental batteries were designed to deliver a 

constant power of 22 W for 2.5 hr with a minimum voltage of 

13 V. When discharged at the maximum expected power 

output of 38.5 W, the batteries operated for 103 min of 

discharge time, achieving a specific energy of 130 Wh/kg. 

This report summarizes design details and safety 

considerations. Results for field trials and laboratory testing 

are summarized. 

Introduction 

In 2007, NASA Headquarters gave the NASA Glenn 

Research Center (GRC) Electrochemical Branch the 

opportunity to demonstrate various elements of the 

Exploration Technology Development Program (ETDP) as a 

part of the 2007 Desert Research and Technology Studies (DRATS) activity at Cinder Lake, Arizona. Early in the project, 

it was decided that electrolytes, developed by the NASA Jet 

Propulsion Laboratory (JPL) under the ETDP for lowtemperature lithium-ion applications, represented the best 

choice for this demonstration timeframe. Milestones of the 

demonstration project are summarized below. 

2007 HIGH-LEVEL SCHEDULE: 

 Fabrication/qualification testing—May through lateAugust 

 Internal GRC Concepts/Safety Review—July 17 

 Johnson Space Center (JSC) Readiness Review— 

August 8 

 “Dry Run” at JSC—August 13–17 

 Final Safety & Readiness Review—August 21 

 Desert RATS field trial—September 10–14 

The principle objective was to demonstrate performance of 

an experimental lithium-ion battery employing advanced 

NASA electrolyte technology. This was done in conjunction 

with the D-RATS EVA spacesuits. Two different suit models 

were available for field trials: the I-Suit and the Mark III suit. 

The experimental battery powered the coolant circulation 

pump which forms a part of the D-RATS liquid air backpack 

(LAB or “Cryopac”). A commercial lithium-ion battery had 

been used to power the LAB in prior years. The demonstration 

battery was designed to be interchangeable with the 

commercial lithium-ion battery. Project objectives included: 

 Demonstrate performance of a lithium-ion battery with 

ETDP-developed NASA electrolyte 

 Support field trials with the Desert Research and 

Technology Studies (D-RATS) EVA LAB 

 Complement field test data with laboratory testing under 

controlled-temperature conditions 

A successful dry run was conducted at JSC, on the week of 

August 13, 2007. The dry run battery, containing NASA 

electrolyte, performed as expected in the LAB. Three field 

trials were successfully completed at Cinder Lake on 

September 10–12, 2007. EVA’s of up to 1-hr and 50-min were 

supported, with residual battery capacity sufficient for 30-min 

of additional run time. 

Battery Design 

Requirements 

The experimental batteries were required to support the 

LAB power system for a planned run time of 2 hr. The power 

system was originally designed to be compatible with a 

commercial, lithium-ion camera battery (IDX, Endura E50S) 

which had a nominal capacity of 3.3 Ah. Key elements and 

power requirements for the D-RATS LAB are illustrated in 

Figure 1. 
NASA/TM—2010-216906 2 

Figure 1.—LAB Power System Block Diagram.1

The battery voltage window of 13 to 16.8 V was consistent 

with four Li-ion cells in series. Power levels and DC/DC 

converter efficiencies were used to estimate battery power 

requirements as shown in Table 1 (current is computed for a 

battery voltage of 12 V). 

TABLE 1.—BATTERY POWER CALCULATIONS 

 Net, 

W 

Efficiency Gross, 

W 

Amps at 

12 V 

Data system 2 100% 2.0 0.17 

Audio DSP 5 83% 6.0 0.50 

Pump nominal 11 79% 13.9 1.16 

total 18 Nominal 21.9 1.83 

 

Data system 2 100% 2.0 0.17 

Audio DSP 5 83% 6.0 0.50 

Pump max 24 79% 30.4 2.53 

total 31 Maximum 38.4 3.20 

Sample Calculations 

Battery capacity was selected to deliver the nominal power 

level of 22 W, for 2.5 hr—allowing a 20 percent margin for 

run time. This requirement translates to a total energy of 

55 Wh. Assuming an average discharge potential of 3.6 V/cell, 

the target cell capacity is 3.8 Ah: 

55 Wh / (3.6 V/cell · 4 cell) = 3.8 Ah 

The target capacity was 15 percent greater than the nominal 

capacity of the 3.3 Ah commercial battery. Average nominal 

current was computed to be 1.5 A (= 3.8 Ah/2.5 h). The 

maximum discharge current of 3.2 A (see Table 1) 

corresponded to approximately a 1C rate. 

 

1

Graphic courtesy of Craig Bernard, JSC 

Figure 2.—Battery location on I-Suit LAB. 

Physical Design 

The experimental battery was designed to be physically 

interchangeable with the commercial battery. This precaution 

minimized risk: if any problems developed with an 

experimental battery, the commercial battery could be rapidly 

substituted in the field. Of course, battery fit within the LAB 

was a critical consideration in the physical design. Battery 

location on the LAB is illustrated in Figure 2. 

The battery location was at the base of the LAB, close to 

the small of the suit-subject’s back. Although there was no 

battery compartment per se, the space available for the battery 

was limited—particularly in thickness and width. The open 

compartment provided some latitude in battery length (the 

vertical dimension in Fig. 2). Dimensions of the experimental 

and commercial batteries are compared in Table 2. 

TABLE 2.—BATTERY DIMENSIONS 

[In millimeters.] 

 IDX 

E50S 

Target Actual experimental 

battery 

Width 86 92 76 

Length 144 144 150 

Thickness 34 48 39 

A side-by-side comparison of the experimental battery and 

the IDX commercial battery appears in Figure 3. 

~ 8 VDC

Power System for the

MarkIII/I-suit D-RATS Cryopac

• Block Diagram

Power box.

Battery

and mount

Hardline

power supply

DC/DC

converter

Adjustable

DC/DC

converter

Loads

Cryopac

data system

Audio DSP

Pump

13 to 16.8 VDC

Ultra

Capacitors

12 VDC

Bat. on/off

Pump on/off

Sources

2Watt

5Watt

11-24Watt
NASA/TM—2010-216906 3 

Figure 3.—Experimental and commercial batteries. 

A commercially-available battery adapter plate (IDX part 

no. ANH2E) served as a base for the experimental batteries. 

This element guaranteed physical and electrical compatibility 

with the existing LAB battery interface. The IDX adapter was 

very well suited to the dimensions of the selected Li-ion cells 

and could be utilized with minimal modification. Details of 

the modified adapter and printed circuit board (PCB) appear in 

the Appendix. The finished batteries were 10 mm narrower 

than the commercial unit, with only a 5 mm increase in 

thickness. 

The individual cell weighed 80 g. The dimensions 

(excluding tabs) were: thickness: 28.5 mm, width: 50 mm, 

length: 103 mm. 

Cell Selection 

Cells for the experimental battery were prepared by 

Quallion, LLC, Sylmar, California. Quallion was selected, 

based on open competitive solicitation. Details of the 

solicitation appear in the Appendix. 

The Quallion, 4.5 Ah, prismatic pouch cell (part no. 

QL4500A) was developed for the U.S. Army 

Communications-Electronics Research, Development, and 

Engineering Center (CERDEC), under the “Ultra Safe High 

Energy Density Rechargeable Soldier Battery” program to 

address needs for soldier systems and equipment applications 

(Ref. 1). A key consideration in the selection of the Quallion 

cell was the availability of safety test data for the existing cell 

construction which was to be delivered. These cells met other 

specifications for fit and capacity. 

Four-cell packs and individual cells were prepared using 

two different formulations of JPL electrolyte (see Appendix). 

These differed in solvent composition as shown in Table 3. 

The control electrolyte was provided by Quallion. Quallion 

performed an analysis of the electrolytes received from JPL. 

These results compare to a Quallion specification <20 ppm for 

acid and water. The acid level in both electrolytes exceeded 

the Quallion specification of 20 ppm. This was not believed to 

represent a safety issue. The acid level in the JPL5 sample was 

two-times higher than observed in JPL2 (see Table 4). 

TABLE 3.—EXPERIMENTAL ELECTROLYTE COMPOSITION 

Designation Composition, by volume 

JPL 2 1.0M LiPF6 in EC+DEC+DMC+EMC (1:1:1:2) 

JPL 5 1.0M LiPF6 in EC+EMC+MP (1:3:1) 

Control 1.0M LiPF6 in EC+DEC+EMC 

Note: see Appendix for explanation of abbreviations and number of cells 

TABLE 4.—QUALLION ANALYSIS OF 

JPL ELECTROLYTES 

Electrolyte HF, 

ppm 

Water, 

ppm 

Conductivity, 

S/cm 

JPL-2 41 5.92 8.90E-03 

JPL-5 78 5.49 9.73E-03 

Figure 4.—Adapter plate with safety-system elements. 

Internal Safety Features 

Experimental batteries included built-in protection for overcurrent, over-discharge and over-temperature. These 

protection elements were mounted on a printed circuit board, 

housed within the battery adapter plate (see Fig. 4). 

A replaceable, 4 A fuse protected the experimental batteries 

against over-current, and provided a means for manually 

disconnecting the cells from the power pins when the battery 

was not in use. Protection against over-temperature was 

provided by a nonreplaceable, 72 °C (maximum) thermal fuse. 

Tests of the thermal fuse showed an average opening 

temperature of 70 °C. A portion of the negative current trace 

on the printed circuit board served as a current measuring 

shunt. Shunt resistance was calibrated to be approximately 

2.5 m. 

A simple voltage-monitoring circuit was developed to 

prevent over-discharge of the battery. The circuit used a 

miniature relay to interrupt current flow to the power output 

terminals if battery voltage was <12 V. Once open, the circuit 

had to be reset manually. When active, the safety circuit 

components drew ~20 mA. Circuit cutoff voltage was 

measured at the cell pack tabs. The target cutoff voltage was 

12 V, based on a lower cutoff voltage limit of 3 V/cell. The 

4.5 Ah Quallion cells could be safely discharged to 2.5 V/cell. 

A schematic of the circuit appears in the Appendix. Field trial 

fuse 

housing 

voltage 

comparator

thermal 

fuse

relay

shunt 

lead

adapter 

power pins

fuse 

housing 

voltage 

comparator

thermal 

fuse

relay

shunt 

lead

adapter 

power pins
NASA/TM—2010-216906 4 

versions of the experimental battery included two LEDs to 

indicate the state-of-charge (SOC) of the battery. These 

indicators provided “at-a-glance” status checking during field 

trials and would signal the end of useful battery life. LEDs 

were connected to the power output terminals of the adapter 

plate through zener diodes. Both LEDs were illuminated when 

the battery voltage was greater than ~15 V, or ~70 percent 

SOC. The last LED extinguished at ~14 V or ~25 percent 

SOC. The LED display was always on, as long as the safety 

circuit was active (power connected to the output terminals). 

The combined parasitic current drain of the safety circuit 

and display LEDs was less than 54 mA with battery at a full 

SOC. This corresponds to <2 percent of the battery capacity 

during the anticipated run time of 2 hr. The safety circuit and 

status LED electronics were all tested for functionality on an 

experimenters breadboard before being assembled into a 

printed circuit. 

Data Acquisition 

Two separate data loggers were selected for collecting 

battery data during field trials. A Pace Scientific, model 

XR440, logger recorded battery volts, current and ambient 

temperature (weight 158 g). An Omega, model OM-CPTC4000, logger was used to log cell core temperature (weight 

27 g). These loggers (see Fig. 5) used internal batteries. 

Battery voltage was scaled to the 0 to 5 V range of the Pace 

logger by means of a voltage divider. The divide-by-four 

resistor pair (34/102 k) was potted inside the head shell of 

the 9-pin data connector. This approach eliminated risk of 

external short-circuiting. The PACE logger included an 11 mV 

channel for monitoring current. 

Electrical connections to the battery were facilitated by 

using a quick-connect, sub-D 9-pin connector mounted at the 

base of the battery. The data connectors included pins and 

sockets compatible with K-type thermocouples for accurate 

battery core temperature measurement. The 9-pin connector 

also provided leads to the individual cell terminals. These 

leads were used to monitor individual cell voltage and for cell 

balancing during charge. 

Figure 5.—Data Loggers, shown 

with 1-in. grid. 

Battery Assembly and Pre-Ship Testing 

Four-cell packs of cells were delivered by Quallion with 

inter-cell, series connections and voltage monitoring leads in 

place. A K-type thermocouple was installed between the 

center cells to provide a measure of battery core temperature. 

The cell bundles were bound together with Kapton tape. Five 

of these pre-wired cell bundles were purchased: two with JPL5 

electrolyte, two with JPL2 electrolyte and one with control 

electrolyte. 

Each cell pack was tested as a free-standing unit before 

being assembled into a battery. Due to tight time constraints, 

battery testing was limited to two discharges at the maximum 

power condition of 38.4 W (intended to represent a worst case 

evaluation). An initial discharge was completed with the cell 

pack electrically connected to the safety circuit but not bonded 

to the PC board. Following a successful test of the cell-pack 

and PC board, the battery elements were built into a finished 

assembly and tested again to verify performance under the 

maximum power rate. In each case, the batteries were charged 

using the same equipment that would be used in the field. This 

testing verified that the battery would deliver expected 

capacity with satisfactory temperature rise under continuous 

operation at the maximum power requirement. The function of 

the over-discharge circuit and voltage-indication LEDs was 

also confirmed as a part of this testing. 

The first two batteries, built with control and JPL5 

electrolyte, provided experience with assembly techniques and 

materials. These batteries were also used during the August 

dry-run trials at JSC. The quantity of potting material—used 

to mechanically immobilize the cell pack inside the battery 

housing—was reduced in the field trial batteries, based on 

experience with the dry run samples. This produced a mass 

savings of approximately 20 g, and increased the specific 

energy to 130 Wh/kg. Width and length dimensions were 

dictated by the outside dimensions of the IDX adapter plate. 

Slight variability in battery thickness was due to variation in 

the hand-formed aluminum battery cover. Characteristics are 

summarized in Table 5. 

TABLE 5.—EXPERIMENTAL BATTERY CHARACTERISTICS 

[Testing Performed Under Maximum Power (38.4 W) Discharge 

Conditions at 23 °C Ambient Temperature.] 

Battery Control JPL5-1 JPL5-2 JPL2-1 JPL2-2 

Battery use Dry run Field trials 

Pack 6/25/07 6/25/0 7/10/0 7/10/0 7/10/0

Assembled 8/3/07 8/6/07 8/31/0 8/29/0 8/29/0

Mass, g 519.9 522.1 498.8 501.8 498.5 

L, mm 150 150 150 150 150 

W, mm 76 76 76 76 76 

T, mm 38 38 39 37 37 

Run_Time, h 1.67 1.72 1.71 1.73 1.71 

Capacity, Ah 4.50 4.61 4.57 4.63 4.59 

Energy, Wh 64.36 66.38 65.83 66.68 65.91 

Sp. Energy 124 127 132 133 132 

Tmax, °C 32.1 35.1 34.1 37.0 35.3 

Circuit cutoff 12.27 12.15 12.16 12.22 12.13 
NASA/TM—2010-216906 5 

Battery assembly was completed in one day. First, the cell 

pack was completely discharged to minimize cell thickness 

and to enhance safety during assembly operations. After the 

individual cell voltages were recorded, the positive and 

negative power leads (16 AWG) were trimmed and soldered to 

the PC board/adapter assembly. The cell pack was then 

bonded to the surface of the PC-board, using a thermallyconductive, silicone adhesive (Chomerics T646). This material 

served as a heat transfer agent and gap filler between the cellpack and the aluminum cover. Leads for individual cell 

balancing were connected to female 9-pin connector along 

with leads for the built-in thermocouple and current-measuring 

shunt. With the cell pack in place, the adapter flange was 

bonded to the adapter base with 3M Scotch-weld 2216 epoxy. 

Immediately after this step, the exposed face of the cell pack 

was coated with a layer of Chomerics T646 and the aluminum 

battery cover was pressed in place, fastened to the adapter 

with Scotchweld 2216 epoxy and screws. The electronics 

section of the PC board was partially filled with expanding 

urethane foam to encapsulate the lead wires and cell tabs and 

the aluminum end covers were fastened in place. Cell voltages 

were measured to confirm that connections had been properly 

made and the clamped assembly was allowed to cure 

overnight. The battery assembly is illustrated in cross-section 

in Figure 6. 

Photographs illustrating battery assembly appear in 

Figures 7 to 10. 

Figure 6.—Battery assembly cross-section. 

Figure 7.—Battery components soldered together. 

Figure 8.—Heat transfer/gap filler applied to exposed face of 

cell-pack. 

Figure 9.—9-pin data connector inside front cover. 

9-pin connector for data 

and charge control

aluminum cover 

fastened to 

adapter plate

4-cell bundle 

bound with 

Kapton tape

power leads 

soldered to PC 

board

IDX 

adapter 

with PC 

board

1.55 in.

(39 mm)

5.94 in. 

(150 mm)

electronic 

components

9-pin connector for data 

and charge control

aluminum cover 

fastened to 

adapter plate

4-cell bundle 

bound with 

Kapton tape

power leads 

soldered to PC 

board

IDX 

adapter 

with PC 

board

1.55 in.

(39 mm)

5.94 in. 

(150 mm)

electronic 

components
NASA/TM—2010-216906 6 

Figure 10.—Finished experimental battery. 

Figure 11.—Field-charging equipment. 

Field Charging Equipment 

Equipment for field-charging the experimental batteries was 

assembled in-house. Two components made up the charging 

control system. First, a voltage monitor used digital process 

controllers to display battery temperature and individual cell 

voltage. The voltage monitor contained a current interruption 

relay to halt charge if any cell exceeded the voltage limit of 

4.25 V or if temperature exceeded 40 °C. An 8 , 50 W power 

resistor was included to facilitate battery discharging 

operations. This function was useful for determining residual 

capacity after field trials and for discharging cells to a safe 

state-of-charge for shipping. Second, a cell balancing module 

automatically limited individual cell voltages to the desired 

control limit of 4.2 V. This unit was previously developed for 

lithium-ion cell testing and was available off-the-shelf 

(Ref. 2). These components are illustrated in Figure 11. 

A 17 V/3 A dc power supply provided the appropriate 

constant-current/constant-voltage charge control. For safety, 

batteries were housed in a covered steel box during field 

charge/discharge operations. 

Field Trials 

Pre-Trials Safety Review Process Overview 

As a NASA program with high visibility and media 

coverage, proposed D-RATS technology demonstrations are 

approved for field trials only after a stringent, formal safety 

review process is completed and reviewed by the JSC team’s 

Experiment Review Board (ERB). The safety review process 

is an especially critical step in the overall selection process for 

technologies such as this experimental battery performance 

demonstration, which is to be interfaced with and integrated 

into the power system for a human-worn I-suit backpack. In 

addition to the inherent safety of a proposed technology 

demonstration, the associated hardware must not interfere with 

suited test subject communications or other electronic 

equipment. 

Principal Investigators were provided with specific 

responsibilities and guidance from the ERB with respect to 

required documentation for D-RATS hardware and test 

activities. At eight months prior to a proposed field trial at the 

Cinder Lake, Arizona site, a written, detailed technical 

overview of the proposed demonstration, including an 

identification of any associated safety concerns, was required. 

At four months prior, evidence was to be provided to the ERB 

that a successful level of laboratory-based testing had been 

achieved to allow for the dry-run activities at JSC. This 

evidence was to include a formal Hazard Analysis Report 

(HAR) for all hardware systems. At one month prior, a final 

“state-of-readiness” presentation to the ERB was required for 

the ERB to make a “go/no go” decision for participation in the 

field trial. 

In response to both the ERB’s and GRC’s strong 

commitments to safety and D-RATS program compliance, 

initiatives were taken within the Electrochemistry Branch both 

to formalize the internal GRC review process and to 

complement and expand upon safety credentials for the 

proposed battery demonstration. In accord with GRC 

recommended practices, an internal review team was 

assembled, which embodied participants from the GRC Safety 

& Mission Assurance Directorate, the GRC Engineering and 

Technical Services Directorate and a lead battery engineer 

from JSC. 

On July 17, 2007, a formal Concepts & Safety Review was 

held at GRC. At this review the technical concept, hardware 

safety attributes, laboratory testing results and proposed 

demonstration activities were presented, as was a formal GRC 

Hazard Analysis Report document, per GRC Systems Safety 

& Reliability Branch guidelines. Following the review, any 

technical questions or issues that remained were addressed, as 

were suggestion pertaining to the internal review process. 

Between this formal review and the dry-run activities at JSC, 

in-house laboratory performance testing of the batteries, 

protection circuitry, data monitoring hardware and the battery 

charging hardware continued. Also during this interval, a 

formal HAR Tracking Verification Log was established, and 

all items on such were closed-out. The HAR document served 

to identify potential hazards, causes, effects, risks, controls 

and verification procedures. 

Following the dry-run activities at JSC, initiatives were 

taken within the Electrochemistry Branch to complement and 

expand upon safety credentials and documentation for the 

proposed battery demonstration. These initiatives included: 

Voltage monitor Cell-balancing module 
NASA/TM—2010-216906 7 

(a) A document addressing the detailed field measures for 

battery inspection, handling and operational procedures 

was generated and approved by GRC technical 

management. 

(b) An informational handout covering the specific GRC 

battery hardware and associated safety and handling 

guidelines was prepared for distribution to D-RATS 

field trial personnel. 

(c) MSDS documents and a basic “lithium-ion battery 

safety” seminar presentation compiled by JSC battery 

personnel were assembled for distribution. 

(d) Quallion performed additional safety and abuse tests on 

the battery’s pouch cells that employed the NASA JPL 

experimental electrolyte. 

(e) A response was made to GRC Research & Technology 

Directorate management pertaining to “lessons learned” 

and suggestions for a formalized internal review 

process for future D-RATS demonstration initiatives. 

On August 21, 2007, the final Desert RATS Safety & 

Readiness Review was held at GRC with Space Flight 

Systems Directorate management personnel in attendance. No 

outstanding technical, programmatic or safety issues or needed 

actions were identified, and written documentation of a 

successful assessment of the review was generated by GRC 

Advanced Flight Projects Office management for transmittal 

to the JSC ERB. The ERB made an affirmative decision for 

the battery technology demonstration at the Cinder Lake, 

Arizona field trial and for shipment of the demonstration 

hardware to the USGS facility in Flagstaff, Arizona. 

August 2007 Dry-Run at JSC 

The first batteries (control and JPL5-1) were used for dryrun activities at JSC during the week August 12, 2007. The 

control electrolyte battery was used for checkout of field 

instruments. All suit trials were performed with battery 

JPL5-1. Fit and function was verified and the dry run battery 

(containing NASA JPL5 electrolyte) performed as expected in 

three trials, including the I-suit as well as the Mark III suit. 

This was also the first opportunity to work with the data 

loggers. A day-by-day history follows. 

Day 1: Fit and Function Test With I-Suit on Stand 

Tests were conducted with the Cryopac attached to the 

upper torso of I-Suit (see Fig. 12) with cooling garment 

connected to pump. Battery functioned as-expected. 

 Battery fit confirmed 

 Pump switches normally to battery power 

 31-min run time 

 Loggers on CAI pack, configured to transmit battery 

voltage data in real time 

Figure 12.—Upper torso of I-Suit with Cryopac. 

In this trial, the data loggers were mounted to a radiotransmitting, Communications, Avionics and Informatics unit 

(CAI pack) which was attached to the back of the LAB. The 

CAI pack successfully transmitted logger data in real time. 

Day 2: I-Suit Field Trial 

This was the first field trial with a suited subject. The 

objective of this test was to demonstrate battery operation with 

the LAB and to test the action of the over-discharge protection 

circuit while mounted on the LAB, in the presence of other 

transmitters. Suit-subjects were accompanied by spotters 

during all field trials, for assistance in maneuvering safely 

around field equipment (see Fig. 13). 

Accomplishments: 

 37-min run time with suit subject in the field 

 Continued discharge after EVA to test battery lowvoltage shutoff circuit: circuit functioned normally 

 Battery operated for a total run time of 3-hr 

 Noise observed in voltage logger signal 

The battery operated normally in this trial and overdischarge circuit activated at the desired 12 V cutoff. The 

voltage data logger transmitted data successfully, but the 

values showed considerable noise. Due to operator error, the 

temperature logger was not set up properly and did not record 

data. 
NASA/TM—2010-216906 8 

Figure 13.—Spotter assists suit-subject, in 

I-Suit, to board the Scout rover vehicle. 

Day 3: Mark III-Suit Field Trial Attempt 

This trial was the first attempt with Mark III suit. Note that 

each suit has its own LAB. As in Day 2, the data loggers were 

connected to a laptop computer housed in the CAI pack, so 

that battery data could be transmitted in real time. The CAI 

pack is a separate module that is attached to the back of the 

LAB (see Fig. 14). 

In this trial, the pump failed to operate on battery power 

when line power was disconnected. A commercial battery was 

substituted, per pre-established safety rules, and the EVA was 

completed without the experimental battery. 

Checks of the experimental battery showed that the safety 

circuit had activated. Normal battery voltage was measured at 

the output terminals after the safety circuit was reset. The 

battery was observed to be quite cold to the touch, due to 

liquid air vapor impingement during the suit charging 

operation. A partial discharge test, performed with the field 

charging equipment, revealed steady current flow with the 

expected terminal voltage. 

Inspection revealed no flaws in the experimental battery. It 

appeared that something triggered the shutdown safety circuit 

to open the relay, interrupting power to the output terminals. 

The battery was fully charged and stored overnight for the 

final day of testing. 

Day 4: Mark III-Suit Indoor Trial 

Inclement weather forced last-day operations indoors. This 

test was conducted with the Mark III suit, but without the CAI 

pack (see Fig. 15). Data loggers were mounted close to the 

battery compartment. Data was stored, as in previous runs, but 

not transmitted in real time. 

Figure 14.—LAB and CAI pack on Mark III suit. 

Figure 15.—Mark III Suit on stand before day 4 dry run. 

CAI 

Pack 

LAB 
NASA/TM—2010-216906 9 

The battery performed normally with the Mark III suit in 

this test. A full discharge, after the EVA, showed that the 

safety circuit functioned normally, after powering the LAB for 

a total of 2.6 hr. 

Both data loggers operated normally during the final day, 

but noise in the voltage and current signals continued to be 

excessive. The signal from the current shunt output (expected 

to be 4 mV) was impossible to interpret. Battery temperature 

increased normally at the end of discharge reaching 

approximately 30 °C. Data appears in Figure 16. 

Figure 16.—Battery data from dry-run day 4 trial. 

Observations and Actions Taken After the JSC Dry-Run 

The same battery (JPL5-1) was used in all four days of 

testing. Three of the four trials were completely successful. 

Reasons for safety circuit activation on day 3 were not clear. 

The battery performed normally the following day. 

In each trial, the fully-charged and activated battery was 

mounted on the LAB before liquid air was added. This process 

took approximately 20 min to complete. During that time, 

evaporated liquid air was vented close to the battery 

compartment, chilling the battery case so that it was very cold 

to the touch. Vibrations caused by venting air also produced a 

loud, intermittent trumpeting-sound. These vibrations would 

have been transmitted to the battery. Either of these factors 

may have caused a premature shutdown. Low temperature 

could create a dip in battery voltage at start up. Vibration may 

have caused the mechanical relay to open prematurely. 

Alternatively, electromagnetic interference may have caused 

the comparator in the safety circuit to malfunction. Further 

testing was necessary to pinpoint the cause of premature safety 

circuit activation. The problem occurred when the LAB pump 

was first switched over to battery power. 

A voltage-indicating LED display was added to the final 

battery design in response to this shutdown incident. This 

feature provided instant verification of battery voltage at the 

power terminals. In the event of a battery shut down, the LEDs 

would extinguish and the spotters could quickly replace the 

experimental battery with a commercial battery. 

Noise in the voltage logger data was peculiar to operation 

on the LAB. In the laboratory, data quality was quite good. In 

field trials a twisted pairs of wires were used for connection to 

the battery. New data cables were prepared with aluminum 

shielding to minimize EMI in the up-coming field trials. The 

loggers were also sheathed in aluminum. 

The field charging equipment functioned as expected 

during the dry-run activity. 

September 2007 Field Trials 

Three successful field trials were completed between 

September 10 and September 12, 2007 at Cinder Lake in 

Flagstaff, Arizona. Battery charging operations were set up 

approximately 10 miles from the Cinder Lake site, at the 

United States Geological Survey facility. 

Three, newly-prepared experimental batteries were 

available for these trials, designated as: JPL2-1, JPL2-2, and 

JPL5-2. Field trials lasted up to 1.9 hr in duration, consuming 

up to 3.7 Ah of capacity. The three successful trials were all 

conducted with the Mark III suit. A fourth trial, attempted 

with the I-suit on day 3, experienced the same premature 

safety circuit activation that was observed during the dry run 

activity. Details of the field trials are summarized below. 

 

Battery Voltage

10

11

12

13

14

15

16

17

18

10:00 10:30 11:00 11:30 12:00 12:30 13:00

time

Volts

safety circuit 

shutdown

Shunt signal

-20

-15

-10

-5

0

5

10

15

20

10:00 10:30 11:00 11:30 12:00 12:30 13:00

time

mV

Battery Temperature

20

22

24

26

28

30

10:00 10:30 11:00 11:30 12:00 12:30 13:00

time

Temperature

End EVA 

Full 

discharge 
NASA/TM—2010-216906 10 

TABLE 6.—CINDER LAKE FIELD TRIAL RESULTS 

Date Battery 

Suit 

EVA 

time, 

h 

Final 

OCV, 

V 

Delivered 

capacity, 

Ah 

Average 

current, 

A 

9/10/07 JPL2-1 

Mark III 

1.87 14.26 3.71 1.98 

9/11/07 JPL5-2 

Mark III 

1.91 14.42 3.29 1.73 

9/12/07 JPL2-1 

I-Suit 

0.38 on 

stand 

16.42 n/a n/a 

9/12/07 JPL2-2 

Mark III 

1.65 14.52 2.81 1.70 

Delivered capacity values in Table 6 are calculated from the 

actual capacity (measured in the laboratory) and the residual 

capacity that was measured after the field trial. Values for 

average current are computed from the stated EVA time and 

delivered capacity. 

Day 1: Mark III Suit With JPL2-1 Battery 

Data loggers with shielded cables were mounted in the 

LAB close to the battery compartment. The CAI pack was 

mounted to the LAB in this trial, but was not used for real 

time battery data transmission. Voltage indicating LEDs on 

the battery provided immediate indication of battery voltage to 

the spotters and made the option of real time transmission with 

the CAI pack unnecessary. The activated battery and data 

logger location are visible in Figure 17. 

Ambient conditions were very mild during this week of 

field trials. Temperature was approximately 27 °C and the 

conditions were mostly sunny. 

LAB transition to battery power on the suit stand was 

uneventful. The EVA mission plan consisted of driving the 

Scout rover vehicle to specific stations where different tasks 

would be performed by the suit subject. The 2-hr mission 

required one recharge of liquid air to the LAB. The 

experimental battery was required to operate for the entire 

mission. A view of the suit subject on Scout appears in 

Figure 18. 

Shielding of the data cables and loggers significantly 

improved the quality of data that was collected, although some 

noise remained. Sample data appears in Figure 19. 

An initial increase in ambient and battery temperatures (see 

Fig. 19) corresponds to egress from the air-conditioned trailer. 

Changes in incident sunlight on the battery compartment, as 

the rover was navigated around the field, probably produced 

fluctuations in temperature. Battery temperature increased 

gradually at the end of discharge, as expected. Internal battery 

temperature increased to approximately 30 °C at the end of the 

EVA, meeting expectations for heat exchange with the 

environment. 

Figure 17.—Day 1 Field trial with Mark III Suit on stand before 

EVA. 

Figure 18.—Day 1 Field trial, EVA with Scout Rover. 

Day 2: Mark III Suit With JPL5-2 Battery 

The day 2 trial was conducted using JPL2-2. Conditions 

and mission operations were essentially a repeat of day 1 and 

battery performance was as expected. 

Data 

loggers 

Battery with 

LEDs 

visible 
NASA/TM—2010-216906 11 

Figure 19.—Day 1 logger data. 

Day 3: Mark III Suit With JPL2-1 Battery 

On day 3, a third successful trial was completed using 

battery JPL5-2 on the Mark III suit. 

Voltage and current history for the Mark III suit trials are 

superimposed in Figure 20. 

The day 3 EVA was limited to 1.6 hr. All three trials 

displayed a slight reduction in battery current after 

approximately 1.3 hr. This event did not correlate with the 

liquid air recharging process. Suit operators did not make any 

adjustments to the pump speed setting. The reason for current 

change remains unexplained. Noise in the current signal 

continued to be considerable. 

Day 3: I-Suit With JPL2-1 Battery 

Based on the success of the two previous days, it was 

agreed that a parallel trial should be attempted with the I-Suit. 

Battery JPL2-1, which had performed flawlessly on day 1, was 

selected for the I-Suit trial. 

The battery successfully supported the I-Suit LAB, while 

on the stand, for approximately 6-min. After 6-min, the 

operators heard the pump slow down, and noted that the 

battery LEDs were off. The liquid air charging operation was 

still in progress and it was believed that part of the soft I-Suit 

may have inadvertently pushed against the battery fuse button. 

This would temporarily disturb internal connections and 

activate the safety circuit. 

Figure 20.—Battery data with the Mark III Suit. 

Figure 21.—Battery JPL2-1 voltage history on I-Suit. 

A check of the battery showed normal terminal voltage 

after resetting the circuit. The LAB was operated with a 

commercial battery while the liquid air charging procedure 

was completed. A washer was taped around the exposed 

battery fuse button to guard it from accidental contact, the 

safety circuit was reset and the battery was replaced on the 

LAB. Within 1 min of operation on the stand, the battery shut 

off again. The I-Suit EVA was conducted with a commercial 

battery. Voltage logger history for the failed start up appears 

in Figure 21. 

Ignoring the noise in Figure 21, battery voltage falls off 

slightly during the initial start up at 9:53. Current (calculated 

from the millivolt shunt signal) was steady at approximately 

1 A until the circuit tripped. The safety circuit trips at 10:00 

and voltage recovers gradually. Battery voltage is consistently 

>15 V, well above the 12 V shutoff limit. The data cable was 

disconnected from the battery after the safety circuit tripped, 

and the open logger channel drifted to an indicated current of 

6 A. 

10

11

12

13

14

15

16

17

0.0 0.5 1.0 1.5 2.0

Volts

0

1

2

3

4

5

6

Amps

Cinder Lake 9/10/2007

Battery JPL2-1 on Mark III Suit

20

22

24

26

28

30

32

0.0 0.5 1.0 1.5 2.0

Run time (h)

Temperature (°C)

battery

ambient

8

9

10

11

12

13

14

15

16

17

0.0 0.5 1.0 1.5 2.0 2.5

Run time (h)

Volts

-1

0

1

2

3

4

5

Amps

Day 1

Day 2

Day 3

10

11

12

13

14

15

16

17

18

19

20

9:30 9:40 9:50 10:00 10:10 10:20 10:30

Time of day

Volts

0

2

4

6

8

10

12

14

Amps

start trip

re-start

trip
NASA/TM—2010-216906 12 

Figure 22.—Battery temperature history for all four field trials. 

When the battery was removed from the LAB, it was found 

that the aluminum case was very cold to the touch. This is the 

same observation that was made in the failed dry run trial. 

Temperature data showed that battery temperature fell to 

16 °C during the liquid air charging process. Battery 

temperature histories for all four field trials are compared in 

Figure 22. 

Battery JPL2-1 proved to be only 8 °C cooler when 

operated on the Mark III suit on day 1. The successfully 

operated batteries on days 2 and 3 were also chilled during the 

liquid air charging process with battery temperatures only 3 °C 

warmer than in the failed trial. In fact, battery JPL2-1 warmed 

slightly during the interim checks and the addition of the fuse 

guard. During the second attempt to start the Lab on battery 

power, the core temperature had increased to 20 °C. 

Nonetheless, the safety circuit activated again. 

Laboratory testing of the same batteries was completed 

after the field trials, at substantially lower temperatures. 

Results show that the minor chilling observed in the field 

would not trip the safety circuit (see following section). Some 

other factors must be responsible for the premature activation 

of the safety circuit. 

Later, the I-Suit developed problems during the liquid air 

recharging process, while operating on the commercial 

battery. The EVA was terminated early. It is not believed that 

the LAB problems were related to battery shut down. 

Laboratory Testing 

Quallion Abuse Testing 

Supplemental abuse testing was conducted at Quallion 

using retained cell samples. This included nail penetration and 

crush tests on fully-charged samples of cells with JPL 

electrolyte. Four cells of each electrolyte composition were 

evaluated. Results appear in Table 7. 

The nail penetration test did not permanently short circuit 

any of the four cells tested. In contrast, the crush test produced 

a permanent short-circuit in the JPL2 electrolyte cells (OCV 

equal to zero). One of these cells (JPL2-29) caught fire. 

Before and after photographs appear in Figure 23. 

Burning was limited to the region between the crush bar 

and the terminals. Presumably the crush fixture simply 

blocked fire from propagating to the other end of the cell. 

Companion cell JPL2-30 developed a hard internal short but 

did not burn. Cell JPL5-18 also developed an internal short 

circuit (OCV = 0.13 V) but did not burn. The author 

recognizes that these are small sample sizes. It is believed that 

cells of either electrolyte type could burn if short circuited in a 

fully charged condition. 

Figure 23.—Cell JPL2-29 before and after crush test. 

14

16

18

20

22

24

26

28

30

32

8:00 9:00 10:00 11:00 12:00 13:00 14:00

Time of day

Battery temperature (°C)

Day 1 Mark III JPL2-1

Day 2 Mark III JPL5-2

Day 3 Mark III JPL2-2

Day 3 I-Suit JPL2-1

TABLE 7.—QUALLION ABUSE TESTING 

Initial Measurements Pre-Test Measurements Post-Test Measurements

CeII ID

IR

(mohm)

OCV

(V)

Weight

(g)

Thickness

(mm)

Capacity

(Ah)

IR

(mohm)

OCV

(V)

Weight

(9)

Thickness

(mm)

Safety

Test

IR

(mohm)

OCV

(V)

Weight

(g)

JPL2-26 6.47 3.40 80.58 6.93 4.58 6.35 4.18 80.57 7.10 Nail 6.23 4.12 80.56

JPL2-28 6.66 3.40 80.04 6.81 4.57 6.56 4.18 80.04 7.01 Nail 6.35 4.09 80.04

JPL2-29 6.55 3.40 79.86 6.87 4.57 6.59 4.18 79.86 7.05 Crush N/A 0.00 exploded

JPL2-30 6.75 3.40 79.35 6.93 4.55 6.74 4.18 79.35 7.08 Crush 31.20 0.00 78.42

JPL5-01 6.05 3.39 79.43 6.84 4.59 6.00 4.18 79.43 7.04 Nail 5.41 4.01 79.44

JPL5-12 6.07 3.39 79.29 6.82 4.60 6.03 4.18 79.29 7.09 Nail 5.59 4.03 79.28

JPL5-18 6.26 3.40 79.46 6.86 4.57 5.90 4.18 79.46 7.02 Crush 61.00 0.17 77.76

JPL5-16 6.13 3.40 79.50 6.86 4.55 5.99 4.18 79.50 7.10 Crush 15.21 4.03 78.84
NASA/TM—2010-216906 13 

Figure 24.—Experimental batteries at 26 W constant power 

discharge. 

Laboratory Testing of Batteries at GRC 

Following the field trials, experimental batteries and cells 

were evaluated in the laboratory for low-temperature 

performance. Charge/discharge testing was conducted using 

an Arbin Instruments BT2000 battery tester. Cells and 

batteries were enclosed in a temperature controlled chamber 

during evaluation (Tenney Model TUJR). Test temperature 

was confirmed using a calibrated digital thermometer (Omega 

Model 52). Actual test temperatures were controlled to within 

2 °C. 

All charging was conducted at 20 °C, using field-trial 

procedures (C/2 constant current charge to 4.2 V, followed by 

a taper charge to C/20). A 26 W, constant power discharge 

was selected for battery performance testing. This was 

18 percent greater than the nominal power level and produced 

an average discharge rate of approximately C/2.5. Results for 

selected batteries appear in Figure 24. 

Capacity retention at low temperature is similar for all three 

electrolytes. Battery JPL5-2 showed a slight improvement 

over the control and JPL-2 battery, retaining 60 percent of the 

room temperature capacity at –30 °C. 

The batteries were not modified in any way for lowtemperature testing. The electronics and adapter connections 

were just the same as in the field trials. Even at –30 °C, the 

battery voltage did not fall below the 12 V safety circuit 

cutoff-level. This supports the argument that chilling of the 

batteries was not responsible for premature shutdown with the 

suit on the stand. 

Note that the over-discharge circuit, in batteries with JPL 

electrolyte, automatically terminated discharge at 12 V. The 

Control battery had its circuit disabled and could be 

discharged below 12 V. 

Cell-to-cell voltage balance was monitored during these 

trials. The range of cell voltage (highest minus lowest value) 

varied with progress of discharge and temperature. Results 

appear in Figure 25. 

Figure 25.—Cell voltage balance in batteries at 26 W. 

Cell voltage balance was better than 0.3 V in these trials. 

Samples of commercial, IDX Endura batteries were also 

evaluated. Note that the model Endura E50S battery, which 

had been used in previous years, was discontinued by IDX. A 

replacement battery (Model E7S), with capacity similar to the 

NASA experimental batteries, was available in 2007. 

10

11

12

13

14

15

16

17

012345

Capacity (Ah)

Battery Voltage (V)

JPL5-2

JPL2-2

Control

-30°C -20°C

23°C

Battery

1

10

100

1000

012345

Capacity (Ah)

Cell voltage range (mV)

23°C

-20°C

-30°C

(a) data for Control

1

10

100

1000

012345

Capacity (Ah)

Cell voltage range (mV)

23°C

-20°C

-30°C

(b) data for JPL2-2

1

10

100

1000

012345

Capacity (Ah)

Cell voltage range (mV)

23°C

-20°C

-30°C

(c) data for JPL5-2
NASA/TM—2010-216906 14 

Figure 26.—Endura Model E7S battery performance at 26 W. 

Figure 27.—Case-temperature increase of Endura battery 

during 26 W discharge at –15 C. 

Two Model E7S (nominal capacity: 4.8 Ah) batteries were 

evaluated using the 26 W moderate-power profile. An IDX 

Model VL-2 charger was made available by NASA JSC to 

facilitate charging of the Endura batteries. Battery charging 

was performed at room temperature, within 24 hr of discharge 

testing. Discharge capacity results appear in Figure 26. 

The commercial battery, which was not designed to operate 

at low temperatures, polarized to 12 V immediately at –25 °C 

and did not develop any measurable capacity. The Endura 

battery also showed substantial initial polarization at –15 °C, 

but recovered due to self heating and retained 87 percent of 

room temperature capacity. Case temperature increased by 

4 °C during the first 1 Ah of discharge (see Fig. 27). 

Auxiliary Testing 

Electrical components were evaluated as a part of the 

experimental battery development. The over-current 

protection fuse was sized to assure delivery of the maximum 

expected current to the LAB, with consideration for the 

maximum current rating of the Quallion pouch cells. Based on 

Table 1, the maximum power corresponded to 3.2 A at 12 V. 

The maximum current rating of the Quallion pouch cells was 

2C, equivalent to 8 amps (Ref. 3). In testing, the 4 A, fastacting, instrument fuse that was selected for the experimental 

batteries demonstrated a maximum current capability of 7 A. 

Fuse samples were tested at room temperature, using the 

same model of fuse-holder that was selected for the 

experimental batteries. Current was ramped at a rate of 

0.6 A/min. until the fuse opened. Results for two samples 

appear in Table 8. 

TABLE 8.—OVER-CURRENT FUSE TESTING 

 Current at fuse 

activation, 

A 

Resistance, 

m

Run1 6.95 98.4 

Run2 7.11 97.5 

Avg. 7.03 97.98 

The 70 °C thermal fuse, selected for over-current protection 

was also evaluated in the laboratory. Samples were soldered to 

a test board, using heat-sinking techniques planned for battery 

assembly. Samples were equilibrated at 23 °C, then heated at 

1 °C/min. while carrying the maximum LAB current of 

3.2 A. Results for three samples were very repeatable and 

consistent with the 70 °C nominal rating. Results appear in 

Table 9. 

TABLE 9.—THERMAL FUSE TESTING 

Temperature at current 

interruption, 

°C 

Resistance, 

m

Run1 70.73 1.79 

Run2 69.63 1.69 

Run3 69.61 1.60 

Avg. 69.99 1.69 

Laboratory Testing of Cells at GRC 

In addition to the 4-cell packs, individual cells were 

prepared by Quallion for laboratory evaluations. 

Two cells of each electrolyte type were tested at a constantpower level of 6.5 W - equivalent to the 26 W levels selected 

for battery testing. Cell capacity results appear in Figure 28. 

None of the cells tested produced any meaningful capacity 

at temperatures less than –35 °C. Assuming a 2.5 V cutoff, 

cells with control and JPL2 electrolyte retained 50 percent of 

their room temperature capacity at –30 °C. The JPL5 

electrolyte preserved 60 percent of room temperature capacity 

at –30 °C. Companion plots for retained energy plots appear in 

Figure 29. 

Energy plots capture the combined effects of capacity loss 

and polarization, providing a more complete measure of low 

temperature performance. JPL5 electrolyte cells retained 

approximately 48 percent of the room temperature energy at 

–30 °C. This represented a 20 percent improvement relative to 

the control and JPL2 cells, which retained 40 percent of the 

room temperature energy at –30 °C. 

12

13

14

15

16

17

012345

Capacity (Ah)

Volts

data for tw o batteries

25°C

5°C

-15°C

-25°C

0

1

2

3

4

5

6

012345

Capacity (Ah)

Case-temperature increase (°C)

Endura E7S, S/N D132859 at -20°C
NASA/TM—2010-216906 15 

Figure 28.—Capacity retention at reduced temperature. 

Figure 29.—Energy retention at reduced temperature. 

 

2.0

2.5

3.0

3.5

4.0

4.5

0% 20% 40% 60% 80% 100%

Fraction of room temperature capacity (%)

Volts

Control C1

Control C2

23°C

0°C

-35°C -30°C

-20°C

2.0

2.5

3.0

3.5

4.0

4.5

0% 20% 40% 60% 80% 100%

Fraction of room temperature capacity (%)

Volts

JPL2-5

JPL2-7

23°C

0°C

-30°C -35°C

-20°C

-40°C

2.0

2.5

3.0

3.5

4.0

4.5

0% 20% 40% 60% 80% 100%

Fraction of room temperature capacity (%)

Volts

JPL5-2

JPL5-8

23°C

0°C

-35°C -30°C

-20°C

2.0

2.5

3.0

3.5

4.0

4.5

0% 20% 40% 60% 80% 100%

Fraction of room temperature energy (%)

Volts

Control C1

Control C2

23°C

0°C

-35°C -30°C

-20°C

2.0

2.5

3.0

3.5

4.0

4.5

0% 20% 40% 60% 80% 100%

Fraction of room temperature energy (%)

Volts

JPL2-5

JPL2-7

23°C

0°C

-35°C -30°C

-20°C

-40°C

2.0

2.5

3.0

3.5

4.0

4.5

0% 20% 40% 60% 80% 100%

Fraction of room temperature energy (%)

Volts

JPL5-2

JPL5-8

23°C

0°C

-35°C -30°C

-20°C
NASA/TM—2010-216906 16 

Figure 30.—Electrolyte energy-retention comparison. 

At temperatures less than –20 °C, the Control and JPL2 

cells exhibit a noticeable “dip” in the polarization curve. This 

corresponds to self-heating of the cell which reduces 

polarization. Energy retention results for the three electrolyte 

types are compared in Figure 30. 

Conclusions 

This 5-month demonstration effort produced additional data 

for the performance of NASA-developed electrolytes in an 

experimental pouch cell construction. Experimental batteries 

performed successfully in three D-RATS field trials, powering 

the LAB in simulated EVAs approaching 2 hr. A simple 

circuit that was designed to prevent over-discharge of the 

batteries, activated prematurely during preparation of the LAB 

in two trials. The weight of evidence appears to point to an 

EMI issue or interaction with the LAB electrical system 

during the transition from line power to battery power. No 

incidents ever occurred during operation in the field. 

All three of the electrolytes exhibited good retention of 

capacity at low temperature. In general, electrolyte JPL5 

produced less polarization in single cell testing, achieving 

40 percent of the room temperature capacity at –35 °C. No 

significant capacity was delivered at –40 °C under the 

moderate power level selected for these evaluations. 

All of the experimental batteries outperformed the Endura 

battery at very low temperatures. 

The experimental battery was designed to maximize heat 

exchange - in order to minimize temperature rise during field 

trials in Houston and Arizona. In contrast, the Endura battery 

houses cylindrical, 18650-size cells in a heavy plastic case 

which tends to restrict heat exchange with the environment. 

The enhanced heat exchange that was designed into the 

experimental batteries probably limited low-temperature 

performance. 

Inexpensive data loggers selected for field trials produced 

considerable noise. In particular, the battery current signal was 

quite weak and showed interaction with the LAB power 

system while on the stand. Any future attempts will require 

some additional development of the data acquisition elements. 

An amplified current signal would be preferable. 

References 

1. Contract No. W15P7T-05-C-P212. 

2. Reid, et al., “Lithium-Ion Cell Charge Control Unit,” 

2004 NASA Aerospace Battery Workshop, November 

16–18, 2004. 

3. Lithium Ion Battery Packs for Portable Life Support 

System Simulator Proposal prepared for: NASA/Glenn 

Research Center Solicitation No. NNC07194975Q. 

2.0

2.5

3.0

3.5

4.0

4.5

0% 20% 40% 60% 80% 100%

Fraction of room temperature energy (%)

Volts

JPL5-2

JPL2-5

Control C1

23°C

0°C

-35°C

-20°C
NASA/TM—2010-216906 17 

Appendix 

Abbreviations 

EC Ethylene Carbonate 

EMC Ethyl Methyl Carbonate 

DMC Dimethyl Carbonate 

DEC Diethyl Carbonate 

MP Methyl Propionate 

HF Hydrofluoric acid 

Cell and Battery Inventory 

Electrolyte type Single cells 4-cell packs 

Control 4 1 

JPL-2 7 2 

JPL-5 7 2 

Total of 38 cells 

Cell Inspection After Storage 

Cells were stored at room temperature at a 50 percent state-of-charge condition on December, 2008. OCV was measured again 

after 14-months of storage. Results for cells are summarized below. 

cell 12/9/2008 2/9/2010 loss (mV) Observations and remarks 

Q1 3.60 3.60 –4 Normal appearance 

Q2 3.62 3.63 –5 Normal appearance 

Q3 3.66 3.66 –4 Normal appearance 

Q65R 3.66 3.66 –1 Slight wrinkling of pouch material 

 

JPL2_09 3.68 3.68 0 Normal appearance 

JPL2_10 3.67 3.67 –1 Normal appearance 

JPL2_11 3.67 3.67 –2 Slight wrinkling of pouch material 

JPL2_12 3.68 3.68 1 Slight wrinkling of pouch material 

JPL2_13 3.68 3.68 1 Normal appearance 

JPL2_5 3.61 3.62 –5 Slight gassing 

JPL2_7 3.62 3.63 –8 Slight gassing 

 

JPL5_19 3.64 3.62 16 Slight gassing 

JPL5_2 3.57 3.52 46 Moderate gassing 

JPL5_3 3.88 3.80 78 Evidence of extreme gassing 

JPL5_7 3.64 3.63 13 Moderate gassing (cell was dropped during initial inspection) 

JPL5_8 3.55 3.49 58 Moderate gassing 

JPL5_9 3.64 3.62 16 Slight gassing 

JPL5_10 N/A Cell was disassembled for destructive physical analysis 

 

Cells with JPL-5 electrolyte showed substantially greater gassing and voltage loss after storage. This is likely linked to the 

greater HF content that was present in the JPL-5 electrolyte (see Table 4). JPL-5 batteries also showed obvious bulge after storage. 

Photographs of the cells and batteries appear below. 
NASA/TM—2010-216906 18 

Control electrolyte 

JPL-2 electrolyte 

JPL-5 electrolyte 
NASA/TM—2010-216906 19 

Lithium-Battery Solicitation 

Overview 

NASA Glenn Research Center is interested in purchasing a number of small lithium-ion battery packs configured to power a 

portable life support system (PLSS) simulator in a demonstration scheduled for the fall of 2007. The objective of this effort is to 

demonstrate improved battery performance using an experimental electrolyte, which has been developed by NASA for nextgeneration lithium-ion batteries. NASA shall provide a sufficient quantity of the experimental electrolyte for substitution in the 

demonstration cells/batteries. A small number of control cells, with the vendors “standard” electrolyte, will also be required for 

laboratory test comparisons. A vendor having experience with Li-ion battery manufacturing methods shall assemble the 

demonstration batteries. 

The PLSS will be operated in sessions at the NASA D-RATS field trials at Meteor Crater, Arizona in September 2007. In 

previous trials, a commercial lithium-ion camera battery (IDX Endura E-50S) has been used to power this device. A person in the

field wears the D-RATS PLSS during this demonstration. Availability of vendor’s safety qualification data for similar cells and/or 

batteries is essential for establishing safety guidelines for demonstration. Submission of existing data for cell-level abuse-tolerance 

represents a best value for selection. 

The vendor shall deliver pre-wired battery assemblies with power leads and provisions for monitoring individual cell voltages. 

NASA plans to complete the integration of the battery package into a housing that is compatible with PLSS. Consultations with the 

battery vendor will be required to assure that integration in the PLSS meets safety requirements and vendor’s specifications. 

Battery assemblies with internal safety features will be considered a best value for selection. 

Field demonstrations shall consist of powering the PLSS demonstrator. Knowledgeable personnel will conduct all battery 

charging operations in a laboratory-environment. It is planned that individual cell voltage and temperature will be monitored 

closely during charging operations. Cell balancing will be performed manually (if necessary) by discharging cells through the 

voltage sensing leads. An automatic battery charger, which facilitates the charging process, is desirable but not essential. 

What is Required 

Qty. Description Delivery required on or before 

 Demonstration of prior experience with proposed product Delivered with proposal 

 Conceptual drawing of proposed battery assembly Delivered with proposal 

 Safety qualification data package for standard cell Delivered with proposal 

10 Individual cells with vendor’s “standard” electrolyte May 14, 2007 

8 Individual cells with NASA electrolyte June 4, 2007 

1 Battery with vendor’s “standard” electrolyte May 14, 2007 

4 Batteries with NASA electrolyte June 4, 2007 

 Data package for all cell/batteries delivered. Accompanies delivered article 

Assurance of delivery date is essential. Early delivery will be considered a best value for selection. 

Options for Additional Deliverables 

If capacity exists to deliver additional cells/batteries, within the schedule timeframe, please propose this as an option in addition 

to the required deliverables. 

An automated battery charger with built-in cell monitoring could also be an option to the proposal. 

Best-Value Selection Criteria 

 Early delivery of batteries and cells 

 Internal safety features 

 Abuse tolerance data for similar cell designs 

 
NASA/TM—2010-216906 20 

Safety Considerations 

1. Prior data for standard electrolyte cells under abuse conditions is essential for planning and evaluating safety measures for 

field trials. 

2. If the proposed battery cells are of an existing production design, a data package of abuse tests and failure modes shall be 

made available. 

3. If the proposed battery cells are of a unique size or shape, then data for cells of similar construction and identical 

electrode/electrolyte type may be substituted. 

4. At a minimum, batteries shall be sufficiently robust to tolerate a five foot drop onto a concrete floor when fully charged, 

without a safety incident. 

Battery Specifications (Based on Vendor’s Standard Electrolyte) 

1. Discharge capacity: greater than or equal to 4 Ah at a C/2 rate at room temperature 

2. Discharge voltage window: 12 to 17 V 

3. Maximum, continuous discharge current: 4 A 

4. Maximum battery external dimensions (inches): 4.875×3.375×1.375 

5. Operating temperature range (discharge):2

 –40 to 60 °C 

6. Battery specific energy (target) >180 Wh/kg 

7. Seal integrity: no detectable electrolyte leakage for a period of 1 year. 

8. Cell matching within batteries shall be adequate to complete at least 10 room-temperature charge/discharge cycles with 

cell voltage balance maintained at 2 percent or better. 

9. Solder-able power leads: 12 in. length, sized to for maximum current/voltage (8 A/17 V). 

10. Solder-able leads for monitoring individual cell voltage 12 in. length. 

Power and monitoring leads shall be pre-attached to the appropriate cell terminals when shipped. 

Physical Markings 

Each cell and battery back shall carry external markings to uniquely identify components. As a minimum, the following shall be 

included: 

 Name or part number 

 Serial number 

 Typical voltage range 

 Type of Chemistry 

Data Package 

1. Disclosure of cell makeup including separator type, electrolyte composition, electrode composition. 

2. Recommended charging procedures for standard electrolyte. 

3. Individual cell dimensions and mass. 

4. Cell formation data for irreversible capacity loss. 

5. Cell capacity, energy data for first three cycles at 25 °C. 

6. Battery capacity, energy data for first three cycles at 25 °C. 

Cell Qualification Package 

Existing abuse-test data for similar cells. 

 

2

Laboratory testing of the cells shall be conducted in this temperature range. Cell components shall be capable of exposure to these limits without 

physical breakdown. 
NASA/TM—2010-216906 21 

Safety Circuit 

2N2222

10k

RESET

R3

+

NEG. POS.

REF01

2

4

6

10.00 V

LM311

8

4

3

2

7 +

R2 51k -

R1 10k

4 Amp

fast-acting

12 - 16.8 V

- +

72°C

thermal

fuse N.O. N.C. COM

DS2E-S-DC12V

Voltage divider

R1 10

R2 51.1 scaling factor error

61.1 planned 0.83633

actual 0.83816 0.22%

Breadboard Results

Vbatt Ref Input Coil relay mA

16.8 10 14.05 11.81 on 21

15.0 10 12.53 10.29 on 18.8

14.0 10 11.71 9.45 on

13.0 10 10.87 8.62 on 16

12.5 10 10.43 8.19 on

12.1 10 10.11 7.88 on

12.0 10 10.02 7.77 on

11.9 10 9.94 0 off

11.4 10 0 off

11.2 9.8 9.36 0 off

Shut-off Cases

normal avg 95% DoD 5% DoD

cell 1 3 3.6 3.33 4

cell 2 3 3.6 3.33 4

cell 3 3 3.6 3.33 4

cell 4 3 1.2 2.01 0

total 12 12 12 12

Self-discharge time

4.5 Ah

21 mA

214 hrs

8.9 days

Breadboard Results

Input = 0.83816Vbatt - 0.03353

R2

 = 0.99997

0

2

4

6

8

10

12

14

16

10 11 12 13 14 15 16 17 18

Battery Volts

Test Point Volts

V-divider 

Input

Ref.

Relay 

coil

turn-off at 12 Volts
NASA/TM—2010-216906 22 

Printed Circuit Board (Dimensions in Inches) 

PC Board rev. 4

TOP VIEW BOTTOM VIEW (copper side)

2

4

6 2

3

4

7

8

EBC

NO NC COM

51.1 k 10 k

SET

10 k

EBC

2

4

6 2

3

4

7

8

CBE

COM NC NO

51.1 k 10 k

SET

10 k

1.27

2.82

2.52

2.67

5.18

2.23 inside

0.32

0.52

1.62

POS NEG

POS

+

+

-
REPORT DOCUMENTATION PAGE Form Approved 

OMB No. 0704-0188 

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control number. 

PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 

1. REPORT DATE (DD-MM-YYYY)

01-11-2010 

2. REPORT TYPE

Technical Memorandum 

3. DATES COVERED (From - To)

4. TITLE AND SUBTITLE

Experimental Lithium-Ion Battery Developed for Demonstration at the 2007 NASA Desert 

Research and Technology Studies (D-RATS) Program 

5a. CONTRACT NUMBER

5b. GRANT NUMBER

5c. PROGRAM ELEMENT NUMBER

6. AUTHOR(S)

Bennett, William, R.; Baldwin, Richard, S. 

5d. PROJECT NUMBER

5e. TASK NUMBER

5f. WORK UNIT NUMBER

WBS 038957.04.07.02.03.03 

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)

National Aeronautics and Space Administration 

John H. Glenn Research Center at Lewis Field 

Cleveland, Ohio 44135-3191 

8. PERFORMING ORGANIZATION

 REPORT NUMBER

E-17484 

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)

National Aeronautics and Space Administration 

Washington, DC 20546-0001 

10. SPONSORING/MONITOR'S

 ACRONYM(S)

NASA 

11. SPONSORING/MONITORING

 REPORT NUMBER

NASA/TM-2010-216906 

12. DISTRIBUTION/AVAILABILITY STATEMENT

Unclassified-Unlimited 

Subject Categories: 15, 16, 18, and 20 

Available electronically at http://gltrs.grc.nasa.gov 

This publication is available from the NASA Center for AeroSpace Information, 443-757-5802

13. SUPPLEMENTARY NOTES

14. ABSTRACT

The NASA Glenn Research Center (GRC) Electrochemistry Branch designed and built five lithium-ion battery packs for demonstration in 

spacesuit simulators as a part of the 2007 Desert Research and Technology Studies (D-RATS) activity at Cinder Lake, Arizona. The 

experimental batteries incorporated advanced, NASA-developed electrolytes and included internal protection against over-current, overdischarge and over-temperature. The 500-g experimental batteries were designed to deliver a constant power of 22 W for 2.5 hr with a 

minimum voltage of 13 V. When discharged at the maximum expected power output of 38.5 W, the batteries operated for 103 min of 

discharge time, achieving a specific energy of 130 Wh/kg. This report summarizes design details and safety considerations. Results for field 

trials and laboratory testing are summarized. 

15. SUBJECT TERMS

Energy sources; Energy storage; Lithium batteries 

16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF

 ABSTRACT

UU 

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28 

19a. NAME OF RESPONSIBLE PERSON

STI Help Desk (email:help@sti.nasa.gov) 

a. REPORT

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