Lithium Batteries and Supercapacitors

1. Bing Hsieh
The alChemist
The Journey is the Reward
My Journey Toward
Printed Supercapacitors
Based on Graphene

2. Connecting the Dots
1990 - 2002
Conducting
Conjugated
Polymers,
PPV for
OLEDs.
2003 -
2007
Toners &
Cartridge
Recycling
2008 - 2011
Solid
Electrolytes/
Ionic Liquids
for Li
batteries.
2011 - 2014
Printed
Organic
Electronics.
Graphene
Supercaps.

3. Steve Jobs’ Commencement Speech
Stanford University, 2005
I'm pretty sure none of this would have happened
if I hadn't been fired from Apple.
It was awful-tasting medicine,
but I guess the patient needed it.
Sometimes life hits you in the head with a brick.
Don't lose faith.
I'm convinced that the only thing that kept me going was
that I loved what I did.
You've got to find what you love.
And that is as true for your work as it is for your lovers.
Your work is going to fill a large part of your life, and
the only way to be truly satisfied is to do what you believe is great work.
And the only way to do great work is to love what you do.
If you haven't found it yet, keep looking. Don't settle.
As with all matters of the heart, you'll know when you find it.
And, like any great relationship, it just gets better and better as the years roll on.
So keep looking until you find it.
Don't settle.

4. Dendrite Formation in Li batteries
•“Good” SEI formation allows Li+
to diffuse in and out of the anode.
•“Bad” SEI does not allow the flow
of Li+ in and out of the anode due
to both thickness issues as well as
a different chemical makeup
compared to good SEI. Dendritic
growth of metallic Li shorts the
battery after reaching the
cathode.

5. Block Copolymers as Solid Electrolytes
Seeo Inc.
PATTERNS APLENTY
These TEM images show
various morphologies of
polystyrene-
poly(ethylene oxide)
copolymers, doped with
salts, that can be used in
advanced batteries.
Understanding the
factors that control
polymer structure and
ionic conductivity is key
to exploiting these
materials.
PS = red, black & white; PEO = green; salt = blue.
Credit: Nitash Balsara, UC Berkeley (Founder of Seeo Inc)

6. Mechanism of Dendrite Formation
in Li metal Batteries
Synchrotron hard X-ray microtomography experiments on
symmetric lithium–polymer–lithium cells cycled at 90 °C
Credit: Nitash Balsara, UC Berkeley

7. Block Copolymers as Solid Electrolytes
(2008-2011)
Mw = 100K or 200K
50% triblock
No homopolymers
•Anionic polymers can be easily isolated in high purity
•ATRP polymers have ionic and homopolymer impurities and weak ester groups.
•Nitroxide Mediated Polymerization (NMP)
s-BuLi EO
(CH2CH2O)(CH2 CH)
PEG OHHO
Br
O
Br
PEG OO
O
Br
O
Br CuCl2
Me6TREN
(CH2CH2O)(CH2 CH) (CH2 CH)
s-BuLi EO
Br Br
(CH2CH2O)(CH2 CH) (CH2 CH)
<50% triblock

8. Block/Comb Polymers as Electrolyte
D3V
(CH2 CH) (Si
CH3
O)
s-BuLi
Si O SiH CH2CH2R
1-3
(CH2 CH) (Si
CH3
O)
Si O Si CH2CH2RPt cat
Si O SiH H
R
Rh
Si O SiH CH2CH2R
•A powerful modular synthesis of functional block copolymers.
•Achieved quantitative grafting for many pendant groups.
•Wide range of R groups have been incorporated.
•Purification was most challenging, but was solved.
•Highest conductivity achieved is 10-4 S/cm
•A new class of hydrogel materials.
(Si
CH3
H
O) (Si
CH3
O)
R
R
(Si
CH3
O) (Si
CH3
O)
Si O Si CH2CH2R

9. Siloxane Liquid Electrolytes
•Low MW liquid electrolytes
•High Li ionic conductivity
•Reduced flammability
Si (O Si)n
R
R
Si (O Si)n
R
Si (O Si)n
R1
R2
Si (O Si)n
R2

10. Synthesis of Ionic Liquids
N
NR1
R1
R3+
CF3-SO2-N--SO2CF3
X- N+
X-
B-
O
O
O
O
-Commercial materials not stable and did not give much
improvement on conductivity.
-Chemistry is straight forward, but purification was more involved.
-One of the ionic liquid gave 10X improvement of conductivity of a
solid electrolyte to 7 x 10-4 S/cm
X- =

11. Mechanism of Dendrite Formation
in Li ion/Li metal Batteries

12. Mechanism of Dendrite Formation
in Li ion/Li metal Batteries

13. Self-Healing Electrostatic Shield (SHES)
Mechanism
•SEI layer will form once Li metal
contact liquid electrolyte.
•Li ions can diffuse through SEI layer
and deposit on Li surface
•SHES additives (such as Cs ions) will
stay outside of SEI layer
•Formation and stability of SEI layer
are the main factors affecting the
Coulombic efficiency of Li
deposition/stripping processes.

14. CsPF6 prevents dendrite formation

15. Traditional Offset vs Dali (Digital offset)
Thin silicone layer
Substrate
FS
FSFS
FSFS
0)
1)
2)
3)
Hydrophilic
nonimage area
Hydrophobic image area
200nm
Printing
Plate

16. C CH2
OO
(CH2)2
O
O CH
HC
CH CH2
OO
(CH2)2
O
R'O
R
Printed p-OTFT Designs
(2012-2014)
OSC
PEN
Silicon oxynitride SiOxNy
Polyera B2000 etc
Ag Ag
Teflon Dielectric Layer
Ag
Nafion
Contact Modification Layer:
F4-TCNQ
NC CN
NC CN
F
F
F
F
S
S
F F
Si(C2H5)3
Si(C2H5)3
N
CH3
CH3
Nafion
Mobility: 0.04 – 0.2 cm2/Vs (Lit: 1.0 cm2/Vs)
ON/OFF ratio: 500-1000 (Lit: 10,000)
Mobility improved to > 1.0 cm2/Vs using a p-type polymer
2F-TES
ADT
PTAA
B2000

17. Printed n-OTFT Issues
PEN
Silicon oxynitride SiOxNy
Polyera B2000 etc
Ag Ag
Teflon Dielectric Layer
Ag
Nafion (1)Polyera N3000
(2)Serious coffee ring issue.
(3)Low mobility for printed n-TFT: 0.01 cm2/Vs
(5 – 100X lower than p-TFT).
SMOS designs requires similar charge mobility
In both p- and n-type TFTs.
N3000 with polymethystyrene P-typeN-1200 (PDI)

18. CMOS Design by Pairing
CNT with SolGel Metal Oxide
• We demonstrated high mobility all printed p-
TFT based on CNT (1 – 5 cm2/Vs). Using
Polythiophene wrapped CNT inks from Zhenan
Bao’s group.
• We demonstrated high mobility all printed sol gel
metal oxide TFT (10-40 cm2/Vs) on glass.
• Beginning of 2014, the silver nanoparticle ink
from Cabot and Sun Chemicals was discontinued.
• Move onto Graphene.

19. Printed Supercapacitors
Based on Graphene (2014)
1 µm2 area contains about
19 million fused benzene rings!
0.34 nm
3.4 Å

20. 我想生命的意義不光是在解決各
種問題，而是在發揚人性光輝，
縱使這種想法可能只是一種慰籍。

21. What is a Supercapacitor (SC)?
Electrochemical Double Layer Capacitor (EDLC)
1/CT = 1/CA + 1/CB
When CA = CB = C
CT = C/2
𝐸 =
1
4
𝐶𝑉2 =
𝟏
𝟒
(εrε0A/L)V2
P = V2/4R =
𝑉2
4
𝐴
ρ𝐿
Both High energy and Power density requires
(1) High voltage electrolyte materials,
(2) Large electrode surface,
(3) Short Ion diffusion length
High Power density requires
(4) Low resistance electrode material

22. A Typical sandwich-SC (SSC) Cell Assembly
Positive Pole
Negative Pole
Separator
Carbon Electrode
Current Collector
Carbon Electrode
Safety Vent
Sealing Disk
Aluminum Can
Type of Electrolytes:
• Aqueous electrolytes: PVA/H2SO4/H2O (small voltage window of 1.3V)
• Organic electrolytes: N+(Et)4
.BF4
-/CH3CN (large voltage window of 2.5V)
• Ionic Liquids: High voltage window of >4.5V
• Solid state electrolytes

23. Sandwich SC vs In-plan MSC
C ∝ 𝑊 𝑒/𝑊𝑠
C ∝ 𝑡2
t 𝑠 = 20 – 30 µm; t1 = 20-200 µm
C ∝ 𝑡1
𝑡1↑, ion diffusion length ↑,
Charging rate ↓, P ↓

24. Graphene Sandwich vs. In-plan MSC
Substrate
Activated Carbon vs Graphene
Substrate- - -
+ + +
_
_
_
_
_
+
_
_
_
_+
_
-
+
+
Advantages of Graphene for in plan MSCs:
(1) Most conducting of all carbon forms,
(2) large electrode surface
(3) Short Ion diffusion path for superior
frequency response and rate capability (in-plane
ion transport)
(4) high capacitance
+ + + - - -

25. Why Graphene SCs?
• Graphene based MSC showed equal to or higher E density than Li ion batteries.
• 104 X greater in power density than Li ion batteries.
• Rapid charging rate (several seconds) vs > 1h in Li ion batteries.
• >200X greater in cycles life than Li ion batteries.
• Much cheaper and safer than Li ion batteries.

26. Rapidly Up-Trending in SCs and Graphene
$3.5B in 2020
SC market to show
3-4X increase in 5 yrs
Graphene market to show
4-5X increase in 5 yrs

27. Manufacturing Methods of Graphene
GrapheneQuality&Cost
Scalability
Chemical Structure of
Graphene Oxide (GO)
(an insulator).
Greaphene based materials have
become “THE” material Platform
for a wide range of applications

28. Graphene SC and MSC via Direct Laser Writing –
The UCLA approach
•LS line resolution is ~20 µm.
•Graphene oxide layer (3 µm, 10-3 S/cm)
expanded to 7.6 µm (7K layers) after laser
exposure. High conductivity of 2350 S/cm
•No current collector used in both SSC and
MSC.

29. Microsupercapcitors via Lithography –
The Max-Planck-Institute for Polymer Research
Only 15 nm thick
15 graphene Layers
200 um

30. Ragone Plots of graphene SSCs vs MSCs
• Although LSG is 500X thicker than MPG, the LSG-MSC and the MPG-MSC show similar performance
characteristics, indicating superior performance for the MPG-MSC. This could be due to the use of Au
current collector, and increased ion transport with the absence of GO interspatial layer in the MPG-MSC.
• GO is relatively unstable as compare to graphene.
• The energy density of these graphene MSCs are similar to the commercial thin film lithium ion batteries
while maintaining 4 orders of magnitude higher in power density.
Substrate
LSG LSG LSG
330 µm
150 µm
Substrate
AuAuAu
200 µm 200 µm 200 µm70 µm 70 µm
7.6 µm
15 nm
3 µm
Graphene oxide
UCLA – LightScribed GO Max Plank – Mathane Plasma reduced GO

31. Direct Printing: from MSC to Large SC
Direct printing of graphene oxide inks onto a substrate followed by radiation.
Direct printing methods: inkjet, Gravure, flexo, waterless offset, or
Microcontact, followed by optional printing of current collectors
Direct printing should be superior than direct laser writing:
(1) A high throughput manufacturing process which could enable large SC at low cost.
(2) Enhanced stability, reduced leakage current, improved ion transport due to the
avoidance of graphene oxide interspatial layer.
Inkjet printed graphene oxide Inkjet printed graphene Gravuer graphene
Thin Plastic Substrate
Graphene
AgAgAg
Graphene Graphene
Thin Plastic Substrate
Graphene Graphene Graphene

32. • GO synthesis via a modified Hummers route established. GO concentration up to
6.0g/L was prepared.
• We casted GO films of various thickness (1 – 10 µm) on PET.
Free Standing, highly flexible graphene oxide papers (20-60 µm)
have been prepared by suction filtration. These GO papers can be
used to prepare higher concentration GO inks.
• High power 980nm laser (50W) obliterated GO films; while
LightScribe laser (780 nm, 47mW) failed to reduce our GO films.
• 266nm laser effectively reduced GO film.
1cm2 areas written with the 266nm laser.
Resistivity of 100, 20, and 10k Ω respectively
404nm
455nm
266nm
Preliminary Results up to June 2014