Evaluation of TIAX High Energy CAM-7/Graphite LithiumIon Batteries at High and Low Temperatures

by Joshua L Allen, Jan L Allen, Samuel A Delp, and T Richard Jow

ARL-TR-7023 August 2014

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Army Research Laboratory

Adelphi, MD 20783-1138

ARL-TR-7023 August 2014

Evaluation of TIAX High Energy CAM-7/Graphite LithiumIon Batteries at High and Low Temperatures

Joshua L Allen, Jan L Allen, Samuel A Delp, and T Richard Jow

Sensors and Electron Devices Directorate, ARL

Approved for public release; distribution unlimited. 
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11/2013–06/2014

4. TITLE AND SUBTITLE

Evaluation of TIAX High Energy CAM-7/Graphite Lithium-Ion Batteries at 

High and Low Temperatures

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6. AUTHOR(S)

Joshua L Allen, Jan L Allen, Samuel A Delp, and T Richard Jow

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U.S. Army Research Laboratory

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13. SUPPLEMENTARY NOTES

14. ABSTRACT

We evaluated lithium-ion battery cells (standard- and high-loading) from TIAX, LLC to determine the capacity and fade rate

(projected cycle life) at low (–20 °C), room (25 °C), and high temperature (50 °C). Standard-loading cells cycled well at 25 °C

with a fade rate of 0.025% per cycle and a C/20 capacity of 2.21 A·h; the projected cycle life is ~800 cycles with 80% 

capacity retention. At –20 °C, standard-loading cells displayed a lower C/20 and C/5 capacity (1.81 and 1.65 A·h). At 50 °C, 

standard-loading cells had an elevated fade rate of 0.048% per cycle, but are expected to cycle in excess of 400 cycles with 

80% capacity retention. High-loading cells had a C/20 capacity of 2.67 A·h and the capacity loss between 25 and –20 °C was 

more severe (31% vs. 20% for standard-loading), but they had a larger final capacity (1.72 A·h). The fade rate for highloading cells was larger (0.06% and 0.09% per cycle at 25 and 50 °C, respectively) with a projected cycle life of ~350 and 

~250 cycles at 25 and 50 °C. These results indicate that standard-loading cells are ideal for applications where cycle life is 

imperative, while high-loading cells are ideal for high-energy applications (even in extreme conditions) where cycle life is a 

secondary concern.

15. SUBJECT TERMS

CAM-7, Lithium-ion, Li-ion, LiNiO2, high energy density, high temperature battery, low temperature battery

16. SECURITY CLASSIFICATION OF:

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19a. NAME OF RESPONSIBLE PERSON

Joshua L Allen

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301-394-0049

Standard Form 298 (Rev. 8/98)

Prescribed by ANSI Std. Z39.18
iii

Contents

List of Figures iv

List of Tables iv

1. Introduction 1

2. Approach 2

3. Results 4

3.1 Standard-Loading Electrodes..........................................................................................4

3.2 High-Loading Electrodes With/Without Optimized Cell Hardware...............................7

4. Conclusions 10

List of Symbols, Abbreviations, and Acronyms 12

Distribution List 13
iv

List of Figures

Fig. 1 Calculated specific energy (left) and energy density (right) of fixed volume 18650 

cell designs with 5 mA·h cm–2active material loading. Data provided by TIAX.....................2

Fig. 2 Voltage profile and specific capacity of cathode materials with a Li metal anode 

(C/20 rate). Average discharge potential given in parentheses. Data provided by TIAX. ........2

Fig. 3 Room temperature (25 °C, cycles 1–20) and low temperature (–20 °C, cycles 21–24) 

rate cycling and room temperature cycle life testing (25 °C, cycles 25–127) of standardloading cells (2.7–4.2 V)............................................................................................................5

Fig. 4 Room temperature (25 °C) differential capacity of 18650 cells with standard-loading 

electrodes. Cycles 1–100 every 10 cycles shown. .....................................................................6

Fig. 5 High temperature (50 °C) cycle life testing (2.7–4.1 V; Charge: C/2 CC, CV to C/20; 

Discharge: C/5 for 1st and 102nd cycle, 1C for 2nd–101st cycle).................................................7

Fig. 6 Room temperature (25 °C, cycles 1–20) and low temperature (–20 °C, cycles 21–23) 

rate cycling of high energy 18650 cells.....................................................................................8

Fig. 7 Room temperature (25 °C) cycle life testing (2.7–4.2 V; Charge: C/5 CC, CV to 

C/20; Discharge: C/10 for 1st and 52nd cycle, C/2 for 2nd-51st cycle) of high energy 18650 

cells............................................................................................................................................9

Fig. 8 High temperature (50 °C) cycle life testing (2.7–4.1 V; Charge: C/5 CC, CV to C/20; 

Discharge: C/10 for 1st and 52ndcycle, C/2 for 2nd-51st cycle) of high energy cells ...............10

List of Tables

Table 1 Battery specifications and description of testing performed ............................................3

Table 2 Description of testing procedures used to evaluate cell performance ..............................3

Table 3 Capacity and specific energy of standard- and high-loading cells at 25 °C and 

–20 °C with discharge rates of C/20, C/10, C/5, C/2, and 1C ...................................................8
1

1. Introduction

The objective of this effort is to evaluate prototype lithium (Li)-ion battery cells provided by 

TIAX LLC in November 2013 for high and low temperature cycleability in accordance with the 

requirements set forth in Phase II of the Small Business Innovation Research (SBIR) program, 

solicitation topic code OSD09-EP5 (contract number W911QX-12-C-0001). 

Commercial Li-ion batteries are readily available with a specific energy in excess of 

200 W·h/kg. Such batteries are based upon cathode chemistries that typically include lithium 

cobalt oxide (LiCoO2 or LCO) and lithium nickel cobalt aluminum oxide (LiNixCoyAlzO2 or 

NCA). The commercialization of Li-ion battery cells in excess of 200 W·h/kg has enabled the 

development of next-generation plug-in hybrid electric vehicles (PHEVs), hybrid electric 

vehicles (HEVs), and fully electric vehicles (EVs), and has provided power improvements to 

consumer electronics. Although the military requirements for Li-ion battery specifications are 

very similar to those used in EVs or consumer electronics (i.e., greater specific energy [W·h/kg]

and energy density [W·h/L]), there are some notable challenges associated with the military 

implementation of commercial “state-of-the-art” Li-ion batteries. 

Batteries used in military applications must be lightweight, compact rechargeable batteries that 

are capable of operating over a wide temperature range. A critical limitation of commercial Liion batteries is their poor low temperature performance (< –20 °C), due to decreased ionic 

conductivity, and instability at higher temperatures (>50°C), due to the degradation of the 

electrolyte, dissolution of the cathode active materials in the electrolyte, and/or breakdown of the 

cathode materials resulting in steady performance degradation including capacity fade and 

impedance rise in the cells.

The prototype cells provided by TIAX LLC in November 2013 include their patented layeredstructure dopant-stabilized lithium nickel oxide (LiNiO2 or LNO) cathode, referred to as CAM7

TM by TIAX, a graphitic anode, and a proprietary electrolyte. When compared with 

commercially available cathode materials, including lithium manganese oxide (LiMn2O4 or 

LMO), lithium iron phosphate (LiFePO4 or LFP), lithium nickel cobalt manganese oxide 

(LiNixCoyMnzO2 or NCM), LCO, and NCA, CAM-7 based 18650 cells have a higher specific 

energy and energy density (Fig. 1). The low end-of charge potential for CAM-7 (4.3 V vs. Li 

compared to >4.8 V for high voltage materials such as lithium nickel manganese oxide 

[LiNi0.5Mn1.5O4 or LNMO] and lithium cobalt phosphate [LiCoPO4 or LCP]) is beneficial for 

reducing the irreversible oxidation of the electrolyte and thus enables a long-cycle life. The 

higher specific capacity of CAM-7 yields an impressive specific energy when compared with the 

state-of-the art cathodes (Fig. 2). The room temperature performance of the CAM-7/graphite 

system has been well studied and compared with similar cathode materials. This report evaluates
2

the high and low temperature performance of CAM-7/graphite 18650 cells to determine if they 

are suitable for extreme environmental conditions.

Fig. 1 Calculated specific energy (left) and energy density (right) of fixed volume 18650 cell designs with 

5 mA·h cm–2active material loading. Data provided by TIAX

Fig. 2 Voltage profile and specific capacity of cathode materials with a Li metal anode (C/20 

rate). Average discharge potential given in parentheses. Data provided by TIAX.

2. Approach

CAM-7 based 18650 cells were provided by TIAX LLC in two batches. Batch 1 (JA428–JA431) 

consists of four cells (two sets of duplicate cells) with standard-loading electrodes, carbonateLCO

NCM

CAM-7

LFP

LMO

NCA

150

170

190

210

230

250

270

75 100 125 150 175 200 225

Cathode C/20 Discharge Capacity (mAh/g)

Specific Energy (Wh/kg) 

NCA

LMO LFP

CAM-7

NCM

LCO

350

400

450

500

550

600

650

700

750

75 100 125 150 175 200 225

Cathode C/20 Discharge Capacity (mAh/g)

Energy Density (Wh/L) 

2.3

2.7

3.1

3.5

3.9

4.3

0 20 40 60 80 100 120 140 160 180 200 220 240

Specific Capacity (mAh/g)

Voltage (V vs. Li)

CAM-7 (3.85V)

NCA (3.81V)

NMC (3.80V)

LMO (4.02V)

LFP (3.38V)

LCO (3.97V)

2.3

2.7

3.1

3.5

3.9

4.3

0 20 40 60 80 100 120 140 160 180 200 220 240

Specific Capacity (mAh/g)

Voltage (V vs. Li)

CAM-7 (3.85V)

NCA (3.81V)

NMC (3.80V)

LMO (4.02V)

LFP (3.38V)

LCO (3.97V)
3

based electrolyte, and a high porosity separator. Batch 2 (JA402–JA407) consists of six cells 

(three sets of duplicate cells) with high density and high active material loading electrodes, a 

carbonate-based electrolyte, and a high porosity separator. Cells JA402 and JA403 also contain 

an engineered 18650 hardware that improves the specific energy by reducing the weight of the 

inert materials. The specifications of the prototype Li-ion cells are provided in Table 1. The

testing procedures for evaluating the cell performance are provided in Table 2. 

Table 1 Battery specifications and description of testing performed

Cell ID C/20 (A·h/W·h) Cell Weight (g) Test Description

JA428

JA429

2.2/8.1

2.2/8.3

40.36

40.57 RT rate, LT Capacity, RT Cycle Life

JA430

JA431

2.2/8.2

2.1/7.9

40.33

40.38 HT Cycle Life

JA402

JA403

2.7/10.0

2.7/10.0

40.28

40.43 RT Rate, LT Capacity

JA404

JA405

2.7/9.9

2.7/9.9

42.42

42.33 RT Cycle Life

JA406

JA407

2.7/10.0

2.7/10.0

42.25

42.39 HT Cycle Life

Table 2 Description of testing procedures used to evaluate cell performance

Cell ID Testing Procedures

JA428

JA429

RT Rate (25 °C)

• Charge: C/2 CC to 4.2 V, CV with C/20 cutoff

• Discharge: to 2.7 V at C/20, C/10, C/2 and 1C

LT Capacity (–20 °C)

• Charge (at RT): C/2 CC to 4.2 V, CV with C/20 cutoff

• Discharge (at LT): to 2.7 V at C/20, C/10, C/5 and C/2

RT Cycle Life (25 °C)

• Charge: C/2 CC to 4.2 V, CV with C/20 cutoff

• Discharge: to 2.7 V at C/5 1st and last cycle

• Discharge: to 2.7 V at 1C x 100 cycles

JA430

JA431

HT Cycle Life (50 °C)

• Charge: C/2 CC to 4.1 V, CV with C/20 cutoff

• Discharge: to 2.7 V at C/5 1st and last cycle

• Discharge: to 2.7 V at 1C x 100 cycles

JA402

JA403

Improved

Hardware

RT Rate (25 °C)

• Charge: C/5 CC to 4.2 V, CV with C/20 cutoff

• Discharge: to 2.7 V at C/20, C/10, C/5 and C/2

LT Capacity (–20 °C)

• Charge (at RT): C/5 CC to 4.2 V, CV with C/20 cutoff

• Discharge (at LT): to 2.7 V at C/20, C/10 and C/5

JA404

JA405

RT Cycle Life (25 °C)

• Charge: C/5 CC to 4.2 V, CV with C/20 cutoff

• Discharge: to 2.7 V at C/10 1st and last cycle

• Discharge: to 2.7 V at C/2 x 50 cycles

JA406

JA407

HT Cycle Life (50 °C)

• Charge: C/5 CC to 4.1 V, CV with C/20 cutoff

• Discharge: to 2.7 V at C/10 1st and last cycle

• Discharge: to 2.7 V at 1C x 50 cycles

Note: HT = high temperature, LT = low temperature, and RT = room temperature
4

3. Results

3.1 Standard-Loading Electrodes

The first batch of 18650 cells provided by TIAX LLC consisted of standard-loading electrodes 

with a carbonate-based electrolyte. The variable rate testing (Fig. 3) yielded a cell discharge 

capacity of 2.23, 2.12, 2.03, and 1.97 A·h at a discharge rate of C/20, C/5, C/2, and 1C, 

respectively. The corresponding specific energies of these cells were 203, 191, 181, and 

172 W·h/kg at discharge rates of C/20, C/5, C/2, and 1C, respectively. To test the low 

temperature performance, the cells were charged at room temperature (CCCV at C/2 with C/20 

cutoff) and transferred to an environmental chamber that was maintained at –20 °C. The cells 

were allowed to equilibrate for 1 h and discharged at various rates. The cell discharge capacity 

obtained was 1.83, 1.76, 1.66, and 1.39 A·h for discharge rates of C/20, C/10, C/5, and C/2, 

respectively (Fig. 3). After testing the room temperature and low temperature rate performance 

of the cells, the room temperature cycle life was tested to see if the variable rate or low 

temperature had any effect on the cell cycleability. A single C/5 cycle was performed to verify 

the capacity is consistent with the cycles performed during the room temperature rate testing; the 

cells actually displayed a higher C/5 capacity of 2.12 A·h, compared with the 2.09 A·h capacity 

previously obtained. The cycle life of the cell was tested by performing 100 cycles at 1C and 

finally testing the C/5 capacity again to compare with the previous results. The 1C capacity of 

the cells decayed from 1.99 to 1.94 A·h after 100 cycles, a fade rate of ~2.5% over 100 cycles or 

~0.025% per cycle. This indicates the system projects to be capable of ~800 cycles while still 

maintaining 80% of the original capacity. The final C/5 cycle is consistent with the previous 

results with a fade rate of ~2.4% after 100 cycles (2.01 A·h for the final C/5 cycle).
5

Fig. 3 Room temperature (25 °C, cycles 1–20) and low temperature (–20 °C, cycles 21–24) rate 

cycling and room temperature cycle life testing (25 °C, cycles 25–127) of standard-loading

cells (2.7–4.2 V)

To better demonstrate the electrode material’s stability, the differential capacity of the room 

temperature cycle life test was plotted as a function of the full cell voltage. The data in Fig. 4 are 

highly consistent through the 100 cycles with the only change between the individual cycles 

being a slight decrease in the reduction peak at 3.9 V. The loss in capacity observed at 3.9 V is 

likely the cause of the 0.025% per cycle fade rate and may be due to slight structural changes 

within the cathode material or loss of cycleable lithium to side reactions at the anode. It is 

noteworthy that no polarization was observed in Fig. 4, suggesting that stable passivation layers 

were formed and perpetual electrolyte decomposition did not occur (which would lead to 

impedance build-up and cell polarization). 
6

Fig. 4 Room temperature (25 °C) differential capacity of 18650 cells with standard-loading 

electrodes. Cycles 1–100 every 10 cycles shown.

The second set of cells was tested at high temperature (50 °C). High temperature testing is 

commonly used to demonstrate the cell’s overall stability to high temperature (electrolyte 

decomposition kinetics increase with temperature) as well as to accelerate the life cycle of the 

cell. The high temperature testing of cells JA430–JA431 can be seen in Fig. 5. The cells were 

cycled at C/5 for the first and last cycle with 100 cycles of C/2 charge and 1C discharge in 

between. Although the cells were similar in design and content, cell JA431 displayed a lower 

capacity (see Table 1). Due to the differing capacity, and the fact that both cells were cycled at 

the same rate (2A discharge), the efficiency of the cells varied with the lower capacity cell 

(JA431) having a lower efficiency due to the higher discharge rate (1.05C for JA431 vs. 1.1C for 

JA430). The average capacity and efficiency is plotted in Fig. 5 with error bars demonstrating 

the high-low values. The average cell capacity of the first 1C cycle is 1.98 ± 0.02 A·h. After 

100 cycles at 1C, the cell average fades to 1.90 ± 0.01 A·h, suggesting the cell fades at a rate of 

~4.8% total through 100 cycles, or at a rate of 0.048% per cycle. Although the fade rate of 

0.048% per cycle is roughly double the fade rate at room temperature (0.025% per cycle), the 

cells still project to be able to cycle ~400 cycles until the capacity fades to 80% of the initial 

average capacity (~1.58 A·h). 
7

Fig. 5 High temperature (50 °C) cycle life testing (2.7–4.1 V; Charge: C/2 CC, CV to C/20; 

Discharge: C/5 for 1st and 102nd cycle, 1C for 2nd-101st cycle)

3.2 High-Loading Electrodes With/Without Optimized Cell Hardware

Three sets of duplicate cells were provided by TIAX LLC with high-loading electrodes. The first

set of cells (JA402–JA403) included an engineered hardware that improved the overall specific 

energy. Room temperature and low temperature variable rate testing was performed on the cells 

and the results are shown in Fig. 6. The cell capacities at room temperature are 2.67, 2.59, 2.51,

and 2.36 A·h for discharge rates of C/20, C/10, C/5, and C/2, respectively. When the cell was 

reduced to –20 °C, the cell discharge capacity was reduced to 2.14, 2.02, and 1.72 A·h for 

discharge rates of C/20, C/10, and C/5, respectively. The specific energies of the improved 

hardware cells at 25 °C were 240, 232, 221, and 201 W·h/kg at discharge rates of C/20, C/10 C/5 

and C/2, respectively. At low temperature (–20 °C), the specific energy drops to 189, 174, and 

144 W·h/kg for C/20, C/10, and C/5, respectively. A comparison of the variable rate capacity 

and specific energy at 25 °C and –20 °C of the standard- and high-loading cells is shown in 

Table 3.
8

Fig. 6 Room temperature (25 °C, cycles 1–20) and low temperature (–20 °C, cycles 21–23) rate 

cycling of high energy 18650 cells

Table 3 Capacity and specific energy of standard- and high-loading cells at 25 °C and –20 °C with discharge 

rates of C/20, C/10, C/5, C/2, and 1C

JA428/429 Standard-Loading JA420/403 High-Loading

C/20 C/10 C/5 C/2 1C C/20 C/10 C/5 C/2 1C

Capacity (A·h)

25°C 2.23 ‒ 2.12 2.03 1.97 2.67 2.59 2.51 2.36 ‒

–20°C 1.83 1.76 1.66 1.39 ‒ 2.14 2.02 1.72 ‒ ‒

Specific Energy

(W·h/kg)

25°C 203 ‒ 191 181 172 240 232 221 201 ‒

–20°C 164 155 142 112 ‒ 189 174 144 ‒ ‒

The second pair of cells (JA404–JA405) was tested at room temperature for cycle life. Since 

these cells contained high-loading, thicker and shorter electrodes, the transport of Li+ions 

through the electrodes and the separator is hindered and thus the rate performance is reduced. If 

one compares the C/20 and C/2 capacity from Fig. 3 (1.81 and 1.65 A·h, respectively) with the 

C/20 and C/2 capacity from Fig. 6 (2.67 and 2.36 A·h, respectively), the capacity decline when 

increasing the rate from C/20 to C/2 is ~8.8% with the standard-loading cells compared to 11.6% 

for the high-loading cells. Since the high-loading electrodes have diminished Li+ion transport,

the cells are less able to delithiate fully at the point when the cell reaches the end voltage (i.e., 

the cell becomes polarized due to the slower kinetics). Due to the polarization phenomenon, the 

high-loading cells display a higher fade rate compared with the standard-loading cells. The cycle 

life of the high-loading cells is shown in Fig. 7. The capacity of the cells fades from an initial 

capacity (C/2) of 2.40 A·h to a final capacity of 2.32 A·h (after 50 cycles). The fade rate of the 

cells is ~3.3% over the 50 cycles or 0.06% per cycle. With an initial capacity of 2.40 A·h and a 
9

fade rate of 0.06% per cycle, the high-loading cells project to be able to be cycled ~350 cycles 

and still maintain 80% capacity retention (~1.92 A·h).

Fig. 7 Room temperature (25 °C) cycle life testing (2.7–4.2 V; Charge: C/5 CC, CV to C/20; 

Discharge: C/10 for 1st and 52nd cycle, C/2 for 2nd-51st cycle) of high energy 18650 cells

The high-loading cells were also tested for high temperature stability (JA406–JA407). The high 

temperature cycle life results can be seen in Fig. 8. The high temperature cells (50 °C) were 

cycled with a lower upper charging limit (4.1 V vs. 4.2 V for the room temperature cycle life 

testing) in order to limit electrolyte oxidation and therefore display a lower overall capacity when 

compared to the room temperature tests. The initial capacity (C/2) of the high temperature cells 

was 2.34 A·h. After 50 cycles, the cells faded ~4.7% to a final capacity of 2.23 A·h; the fade rate 

was ~0.09% per cycle. Based on the initial capacity of 2.34 A·h and a fade rate of 0.09% per 

cycle, the high-loading cells project to be capable of being cycled ~250 cycles and still maintain 

80% capacity retention at 50 °C. 
10

Fig. 8 High temperature (50 °C) cycle life testing (2.7–4.1 V; Charge: C/5 CC, CV to C/20; 

Discharge: C/10 for 1st and 52nd cycle, C/2 for 2nd-51st cycle) of high energy cells

4. Conclusions

Five sets of duplicate cells were provided by TIAX LLC for evaluation at high and low 

temperatures as part of the requirements set forth in the Phase II SBIR contract. The cells 

consisted of two sets of standard-loading cells and three sets of high-loading cells. The standardloading cells cycled well at room temperature with a fade rate of only 0.025% per cycle and a 

C/20 capacity and specific energy of 2.21 A·h and 203 W·h/kg, respectively. The low fade rate 

suggests the standard-loading cells are capable of up to 800 cycles while maintaining 80% of the 

initial capacity. Although the C/20 capacity of the cells at –20 °C was reduced by only 18% 

(1.81 A·h), the slower ionic conductivity had a more dramatic effect at higher rates, reducing the 

C/5 capacity from 2.09 A·h at room temperature to 1.65 A·h at –20 °C (a 21% reduction). 

The high temperature cycle life of the standard-loading cells faded more dramatically, as 

expected, due to increased electrolyte oxidation and/or structural changes within the 

cathode/anode. With an initial capacity of 1.98 A·h and a fade rate of 0.048% per cycle, the high 

temperature cells are still project to be able to cycle ~400 cycles while maintaining 80% capacity 

retention. The ability of the standard-loading electrodes to cycle at low temperature, as well as 

the impressive cycle life at room temperature and high temperatures, marks an improvement over 

the state-of-the-art Li-ion battery.
11

In order to improve the specific energy of the cells, TIAX LLC provided three sets of cells 

containing higher-loading electrodes. Although these cells do have a significantly higher specific 

energy (240 W·h/kg vs. 203 W·h/kg for standard-loading), the rate performance and cycle life of 

the cells suffer. A summary of the room temperature and low temperature discharge capacity and 

specific energy is shown in Table 3. The capacity of the standard-loading electrodes decreased 

from 2.23 A·h (C/20) to 2.12 A·h (C/5), a decrease of ~4.9%, while the higher-loading 

electrodes decreased from 2.67 A·h (C/20) to 2.51 A·h (C/5), a decrease of 6.0%. Furthermore, 

the low temperature performance of the high-loading cells is worse due to the compounding 

effects of the decreased electrode conductivity, higher current density through the separator, and 

reduced ionic mobility through the higher-loading electrodes. The capacity of the higher-loading 

cells decreased from 2.67 A·h (RT) to 2.14 A·h (at –20 °C) for C/20, a decrease of 20%, and 

from 2.51 A·h (RT) to 1.72 A·h (at –20 °C) for C/5, a decrease of 31%. Comparing the standardloading (20% C/5 capacity decrease) and higher-loading (31% C/5 capacity decrease) cell 

designs, there is a more significant decrease in capacity due to the operation at low temperature 

with higher-loading electrodes. It is notable that even with the larger relative capacity decrease 

of the higher-loading cell compared with the standard-loading cell; the capacity of the cell is still 

larger at 1.72 A·h versus 1.66 A·h for the standard-loading cells (at C/5 discharge). Thus, any 

decrease in rate performance is more than offset by benefits in overall specific energy. 

The room temperature and high temperature cycle life tests for the high-loading cells display an 

initial (C/2) capacity of 2.40 and 2.34 A·h, respectively. The fade rates of the cells were 0.06% 

and 0.09% per cycle for the room temperature and high temperature cells, respectively. With the 

initial capacity and fade rates listed previously, the cycle life of the cells were calculated to be 

~350 and ~250 cycles for the room temperature and high temperature, respectively, while still 

maintaining an 80% capacity retention.

The CAM-7/graphite cells provided by TIAX LLC demonstrate standard- and higher-loading 

electrode designs that could meet the needs of different military applications. The standardloading electrode cell designs display a lower specific energy than the higher-loading designs, 

but have a lower fade rate that enables a significantly longer cycle life (up to 800 cycles with 

80% capacity retention). These cells are ideal for applications where cycle life is imperative, 

even in extreme conditions. The higher-loading cell designs, in contrast, provide a specific 

energy of up to 240 W·h/kg (at C/20 discharge rate) and also display an improved low and high 

temperature capacity. The higher-loading cells, however, suffer from an increased fade rate that 

limits their projected cycle life to ~350 and ~250 cycles (for RT and 50 °C) while maintaining 

80% capacity retention. These cells are ideal for high energy applications (even in extreme 

conditions) where cycle life is a secondary concern. The CAM-7/graphite system is well suited 

for low and high temperature applications and offers many benefits over the state-of-the-art Liion battery cells. 
12

List of Symbols, Abbreviations, and Acronyms

EVs electric vehicles 

HEVs hybrid electric vehicles 

HT high temperature

Li lithium

LiCoO2 or LCO lithium cobalt oxide 

LiCoPO4 or LCP lithium cobalt phosphate

LiFePO4 or LFP lithium iron phosphate 

LiMn2O4 or LMO lithium manganese oxide

LiNiO2 or LNO lithium nickel oxide 

LiNi0.5M1.5O4 or LNMO lithium nickel manganese oxide 

LiNixCoyMnzO2 or NCM lithium nickel cobalt manganese oxide

LiNixCoyAlzO2 or NCA lithium nickel cobalt aluminum oxide

LT low temperature

PHEVs plug-in hybrid electric vehicles 

RT room temperature

SBIR Small Business Innovation Research
13

1 DEFENSE TECHNICAL

(PDF) INFORMATION CTR

DTIC OCA

2 DIRECTOR

(PDF) US ARMY RESEARCH LAB

RDRL CIO LL

IMAL HRA MAIL & RECORDS MGMT

1 GOVT PRINTG OFC

(PDF) A MALHOTRA

4 DIRECTOR

(PDF) US ARMY RESEARCH LAB

RDRL SED C

JOSHUA L ALLEN

JAN L ALLEN

SAMUEL A DELP

T RICHARD JOW
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