U.N. Lithium Battery Working Group
4th Meeting, May 18 – 20, 2010
Washington DC, USA
Change the test sequence of UN 38.3 testing
Submitted by SRICI China
1. The UN tests of T1-T5 simulate the environment of the lithium cells and batteries during the
air transport. In which T3 and T4 simulate the mechanical environment, while T1 and T2
simulate the ambient environment. After the mechanical tests of T3 and T4, the battery may
have some slight defects that cannot be evaluated by the current criteria. Since the batteries
have relative low internal pressure, the slight defects may not induce the leakage or mass loss
in short time. However, it may lead to the following damage of battery after a relative long
time besides the criteria requires. So that it leaves potential risk on transportation. However, if
the environmental tests T2 and T1 conducted after the mechanical tests, these slight defects
may easier exposed since the mass loss or leakage may tend to happen in case of closure of
cells or batteries damaged.
2. For T5 the external short circuit, many measures are taken to protect it when cells or batteries
go for the transport. Mass loss and leakage is permitted in T5. And T5 will have an effect on
the test result of T1 since the voltage may loss after T5. Therefore T5 should be done after T1.
3. In the actual transportation, the mechanical damage may happen before the cells and batteries
exposed to low pressure and extreme temperatures. That means the cells and batteries with
slight defects may exposed to low pressure and extreme temperatures also. Therefore,
conducted T3 and T4 before T2 and T1 may be a better way for simulating the real
transportation.
4. To prove the theory, we set up a test to compare the mass loss conducted in different test
sequence.
First, we choose three types of polymer lithium ion cells with different mass. For each type
we choose 10 pieces cells.
a. Polymer lithium ion cell with the mass of approximate 160 grams;
b. Polymer lithium ion cell with the mass of approximate 15 grams;
c. Polymer lithium ion cell with the mass of approximate 6 grams.
Second, we divide each type of cells into two groups and five cells for each group. Third, we
charge all the cells to fully charged status. Then we conduct the tests, group 1 is from T1 to
T4 and the group 2 is from T3, T4 to T2, T1. All the tests are conducted with the same
equipments and at the same test conditions. For both groups, we haven’t found the defects
such as venting, rupture, leakage, disassembly, fire and voltage drop in the tests. However,
when we compared the data of mass loss, the results are obviously different. The mass loss
after T2 and the total mass loss (after 4 tests) of group 2 is much higher than group 1 (see
attachment 1).
5. The test results confirm the theory that the mechanical tests T3, T4 will influence the
environmental tests T1 and T2. As a conclusion, we think if the current test sequence is
changed to T3 - T4 - T2 - T1, The tests will be more effective and easier to evaluate the
battery defects.
Proposal
6. Based on the above discussion, we will propose to change the current test sequence for UN
testing T1-T2-T3-T4-T5 to T3-T4-T2-T1-T5.
Attachment 1: Test Data
Sample
Test
item
T1
T2
a. Polymer
lithium ion cell
with the mass
of approximate
160 grams
T3
T4
T1-T4
T1
T2
b. Polymer
lithium ion cell
with the mass
of approximate
15 grams
T3
T4
T1-T4
T1
c. Polymer
lithium ion cell
with the mass
of approximate
6 grams
T2
T3
Sort
Group 1
T1-T2-T3-T4
(mass loss %)
Group 2
T3-T4-T2-T1
(mass loss %)
Increase of mass loss
(%)
Maximum
0.0034
-0.0026
-
Minimum
0.0017
-0.0042
-
Average
0.0028
-0.0030
-
Maximum
0.0101
0.0161
58.8852
Minimum
0.0083
0.0127
52.7725
Average
0.0093
0.0140
49.9116
Maximum
-0.0008
0.0015
-
Minimum
-0.0016
0.0006
-
Average
-0.0012
0.0011
-
Maximum
-0.0016
-0.0001
-
Minimum
-0.0029
-0.0008
-
Average
-0.0021
-0.0005
-
Maximum
0.0100
0.0133
33.0093
Minimum
0.0078
0.0100
28.1742
Average
0.0088
0.0115
31.2547
Maximum
0.0034
0.0034
-
Minimum
-0.0007
-0.0027
-
Average
0.0004
-0.0008
-
Maximum
0.0127
0.0168
32.1597
Minimum
0.0101
0.0101
-
Average
0.0110
0.0136
23.2641
Maximum
-0.0007
-0.0013
-
Minimum
-0.0033
-0.0034
-
Average
-0.0017
-0.0027
-
Maximum
-0.0007
0.0034
-
Minimum
-0.0027
0.0013
-
Average
-0.0016
0.0023
-
Maximum
0.0087
0.0148
69.0003
Minimum
0.0074
0.0087
18.3459
Average
0.0081
0.0124
53.4296
Maximum
0.0016
-0.0016
-
Minimum
-0.0032
-0.0143
-
Average
-0.0010
-0.0083
-
Maximum
0.0303
0.0509
67.7837
Minimum
0.0270
0.0411
52.4717
Average
0.0296
0.0464
57.0015
Maximum
0.0079
-0.0016
-
Minimum
-0.0064
-0.0111
-
Average
0.0032
-0.0060
-
T4
T1-T4
Maximum
0.0048
0.0048
-
Minimum
-0.0064
0.0016
-
Average
-0.0013
0.0038
-
Maximum
0.0333
0.0446
33.6940
Minimum
0.0238
0.0269
12.9890
Average
0.0305
0.0359
17.7418
Attachment 2: Test Samples
a. Polymer lithium ion cell with the mass of approximate 160 grams
b. Polymer lithium ion cell with the mass of approximate 15 grams
c.
Polymer
lithium
ion
cell
with
the
mass
of
approximate
6
grams