Flexible Solid-State Lithium-Ion Batteries: Materials and Structures

Round 1

Reviewer 1 Report

In the article, the author mentions that flexible solid-state lithium-ion batteries need to have good mechanical properties, including various deformation modes such as bending, folding, stretching, compressing, and twisting. These mechanical requirements have a significant impact on the selection of battery structure and materials. Can the author further explore how these requirements affect the battery structure and materials, and how to balance mechanical performance with electrochemical performance?

Comments for author File: Comments.docx

Author Response

The impact of mechanical performance requirements on material and structural selection has been added at the end of Chapter 2 and Chapter 3. Analysis of balanced mechanical and electrochemical properties has also been added at the same location.

Reviewer 2 Report

In this review work, the authors reviewed the electrode materials and electrolytes for flexible LIBs. It is well written and may be attractive for the researchers in this field. Besides, it is recommended to implement deep insights into high energy and safety flexible Li-based batteries, from both scientific and industrial points of view. Moreover, the detailed parameters to assess this technology to make difference to the conventional LIBs.

Author Response

In the summary section of Chapter 4, a discussion on the high energy and safety of flexible lithium batteries has been added. In the first introduction section, a comparison between flexible lithium-ion batteries and traditional lithium-ion batteries has been added.

Reviewer 3 Report

The paper presented by Deng and He raises the issue of battery flexibility as a topic of great interest. The review is well documented and brings together a large amount of work on different technologies in the quest for flexible batteries. Although it is well laid out and a lot of work has been done, I recommend its publication after extensive modification and restructuring:

 

1) I find the different sections unstructured. In the part on electrodes containing graphene, it explains what Li-S technology is and then goes on to deal with graphene-doped cathodes and CNTs, although the latter had their previous section. In addition, It should be clearer when such compounds are used in the anode-side or in the cathode-side, not a mixture of the two.

 

2) The size of the figures is not enough to be read. It must me improved for the revised manuscript.

 

3)A review of the manuscript should be carried out to eliminate typographical errors that can be found throughout the text, for example: page 8 line 294 Figure ??

 

4)I believe that polymer gels as flexible electrolytes for this type of device are given too little importance. New references containing such materials should be introduced and explained in more detail:

https://doi.org/10.1021/acs.chemmater.1c02952

https://doi.org/10.1021/acsomega.2c00861

https://doi.org/10.1007/s11581-022-04621-4

Author Response

• I find the different sections unstructured. In the part on electrodes containing graphene, it explains what Li-S technology is and then goes on to deal with graphene-doped cathodes and CNTs, although the latter had their previous section. In addition, It should be clearer when such compounds are used in the anode-side or in the cathode-side, not a mixture of the two.

 

Response:This section has been modified to mainly describe the role of graphene in the cathode.

 

• The size of the figures is not enough to be read. It must me improved for the revised manuscript.

 

Response:All figures have been replaced with larger and clearer versions.

 

• A review of the manuscript should be carried out to eliminate typographical errors that can be found throughout the text, for example: page 8 line 294 Figure ??

 

Response:We have made modifications to this error, as shown in page 8 line 279 Figure 4.

 

4)I believe that polymer gels as flexible electrolytes for this type of device are given too little importance. New references containing such materials should be introduced and explained in more detail:

 

https://doi.org/10.1021/acs.chemmater.1c02952

 

https://doi.org/10.1021/acsomega.2c00861

 

https://doi.org/10.1007/s11581-022-04621-4

 

Response:These references have been organized and added to section 2.2.

Reviewer 4 Report

Recently, flexible solid-state lithium-ion batteries have become increasingly important with the rapid advancement of research in flexible electronics and wearable technology. This manuscript describes a systematic and comprehensive overview of the development of flexible solid-state lithium-ion batteries. To meet the demand for flexible power sources, this manuscript focuses on two main areas: flexible materials and flexible structures. Specifically, it is described the various materials for electrodes such as carbon nanotubes, graphite, carbon fibers, carbon cloth, and conducting polymers, as well as flexible solid materials for electrolytes. Additionally, it is examined for the structural design of flexible solid-state lithium-ion batteries, including one-dimensional fibrous, two-dimensional thin-film, and three-dimensional flexible lithium-ion batteries. By summarizing the advantages and disadvantages of different materials and structures, this manuscript aims to highlight the main challenges for future designs of flexible solid-state lithium-ion batteries and provide a valuable reference for researchers in this field. Therefore, I do recommend the manuscript be published in Energies with some points of minor revisions.

 

Comment 1:

It appears that several sentences in the Materials section are not directly related to the topic of flexible solid-state batteries. For example, the discussion of 2.1.1. Carbon Nanotubes focus on their properties rather than their application in flexible batteries. Furthermore, the 2.1.2 Graphene section is described to discuss the volume expansion in Si batteries and the shuttle effect in sulfur batteries, which is not directly relevant to the topic at hand. It. To improve the focus and coherence of the manuscript, it may be necessary to revise these sections or consider changing the title of the review.

 

Comment 2:

If the resolution of the figures is uniformly low throughout the manuscript, it may be better to replace them with high-resolution versions. By doing so, the details of the figures, such as graphs and images, can be presented more clearly and accurately.

Author Response

Comment 1:

 

It appears that several sentences in the Materials section are not directly related to the topic of flexible solid-state batteries. For example, the discussion of 2.1.1. Carbon Nanotubes focus on their properties rather than their application in flexible batteries. Furthermore, the 2.1.2 Graphene section is described to discuss the volume expansion in Si batteries and the shuttle effect in sulfur batteries, which is not directly relevant to the topic at hand. It. To improve the focus and coherence of the manuscript, it may be necessary to revise these sections or consider changing the title of the review.

 

Response:The description of carbon nanotubes in 2.1.1 has been simplified. The section discussing silicon negative electrodes and the shuttle effect of lithium sulfur batteries in section 2.1.2 has been appropriately deleted. More space is devoted to describing the role of carbon nanotubes or graphene in electrodes.

 

Comment 2:

 

If the resolution of the figures is uniformly low throughout the manuscript, it may be better to replace them with high-resolution versions. By doing so, the details of the figures, such as graphs and images, can be presented more clearly and accurately.

 

Response:All figures have been replaced with larger and clearer versions.

Round 2

Reviewer 3 Report

The authors have taken into account the considerations previously submitted and substantially improved the content of the paper. Therefore, I suggest its publication without further modification.