01
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Preface
Lithium iron phosphate batteries have the advantages of high working voltage, large energy density, long cycle life, good safety performance, small self-discharge rate, and no memory effect. They also support stepless expansion, are suitable for large-scale power storage, and have good application prospects in renewable energy power stations, power grid peak shaving, emergency power systems and other fields. Therefore, lithium iron phosphate has become the mainstream choice for many power battery companies(Figure 1)。
The production quality of lithium iron phosphate is mainly affected by material characteristics, production process and quality control. Among them, metal ion impurities will have different degrees of impact on each component, for example,1)Boehmite used as a flame retardant for power batteries has high requirements for material purity. The presence of impurities will cause changes in its crystal structure, affecting the physical properties of Boehmite such as hardness, density, melting point, and greatly reducing its performance;2) In PVDF (polyvinylidene fluoride, positive electrode binder) and its substitute - CMC (carboxymethylcellulose), if the impurities are incompatible with the matrix or are unevenly dispersed, it will lead to internal stress concentration of the material and degradation of mechanical properties;Or promote its degradation and cross-linking reactions to reduce its thermal stability;3) Metal impurities have complex and multi-faceted effects on the electrode material. For example, larger metal particles will directly pierce the separator, resulting in short circuits of the positive and negative electrodes, and metal impurities will be deposited on the electrode surface through electrochemical and chemical action, greatly affecting the safety performance and service life of the battery.
Therefore, in all aspects of the production of battery modules, accurate detection of metal impurities in raw materials and components is required in a timely manner, providing important guarantees for optimizing production processes, ensuring material and product quality, ensuring production safety and environmental friendliness.
This work adoptsBoo micromate d7 microwave digester(Figure 2)WhereUse samples of important components in the battery to verify the processing effect of this type of instrument.
Figure 2Micromate d7 microwave digester
02
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Dissolve experimental steps
1. Battery component sample description
Table 1 and Figure 3 show the basic situation of each battery component sample.
Table 1. Characteristics and functions of battery module samples
sample | use | Possible metallic impurities |
Erection stone | Battery flame retardant | Thewait |
PVDF (Polyvinylidene Fluoride) | Positive electrode binder | FO, CU, PC, L. L., MN, MNwait |
APP (Ammonium polyphosphate) | Extreme ear diaphragm | Fe 、 ca 、 mg 、 with 、 crwait |
CMC | PVDF alternatives | Fa, c, cr, mi, cowait |
Lithium iron phosphate | Positive electrode material | On, k, mg, mn, cr, ni, cu, zn, ti, vwait |
graphite | Negative electrode material | Fround, CL, Cu, Cu, Mn, Mnwait |
Figure 3 Battery assembly sample
two,Brief description of experimental steps
three,Results and discussion
Figure 4 The appearance of the treated sample
03
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Introduction to the performance of micromate d7 microwave digester
As an efficient, safe and reliable sample pretreatment instrument, the Boo Micromate D7 microwave digester used in this experiment has many advantages:
1. Equipped with MATE-T wireless full tank temperature monitoring system, it can monitor temperature changes and display the change curve in real time;
2. Equipped with MATE-P wireless full tank pressure monitoring system, it realizes non-contact precision pressure monitoring, and tracks the pressure changes of each sample in real time;
3.The digestion tank adopts an active elastic pressure relief protection design to avoid sample pressure overload;
4. With an intelligent control system, all operations can be easily completed and equipped with multiple security functions, making your digestion work safer, more secure, simple and easy!
5.......
More information about micromate d7 microwave digester
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