Benign Recycling of Spent Batteries towards All‐Solid‐State Lithium Batteries

Recent progress of bacterial cellulose-based separator platform for lithium-ion and lithium‑sulfur batteries

Bacterial cellulose (BC) has recently attracted a lot of attention as a high-performance, low-cost separator substrate for a variety of lithium-ion (LIBs) and lithium‑sulfur batteries (LISs). BC-base can be used in the design and manufacture of separators, mainly because of its unique properties compared to traditional polyethylene/polypropylene separator materials, such as high mechanical properties, high safety, good ionic conductivity, and suitability for a variety of design and manufacturing needs. In this review, we briefly introduce the sources, production methods, and modification strategies of BC, and further describe the preparation methods and properties of BC battery separators for various LIBs and LISs.

Recovery of Li and Co in Waste Lithium Cobalt Oxide-Based Battery Using H1.6Mn1.6O4

H_1.6Mn_1.6O₄ lithium-ion screen adsorbents were synthesized by soft chemical synthesis and solid phase calcination and then applied to the recovery of metal Li and Co from waste cathode materials of a lithium cobalt oxide-based battery. The leaching experiments of cobalt and lithium from cathode materials by a citrate hydrogen peroxide system and tartaric acid system were investigated. The experimental results showed that under the citrate hydrogen peroxide system, when the temperature was 90 °C, the rotation speed was 600 r·min^-1 and the solid-liquid ratio was 10 g·1 L^-1, the leaching rate of Co and Li could reach 86.21% and 96.9%, respectively. Under the tartaric acid system, the leaching rates of Co and Li were 90.34% and 92.47%, respectively, under the previous operating conditions. The adsorption results of the lithium-ion screen showed that the adsorbents were highly selective for Li⁺, and the maximum adsorption capacities were 38.05 mg·g^-1. In the process of lithium removal, the dissolution rate of lithium was about 91%, and the results of multiple cycles showed that the stability of the adsorbent was high. The recovery results showed that the purity of LiCl, Li₂CO₃ and CoCl₂ crystals could reach 93%, 99.59% and 87.9%, respectively. LiCoO₂ was regenerated by the sol-gel method. XRD results showed that the regenerated LiCoO₂ had the advantages of higher crystallinity and less impurity.

MnCO3 Cuboids from Spent LIBs: A New Age Displacement Anode to Build High-Performance Li-Ion Capacitors

The advantage of hybridizing battery and supercapacitor electrodes has succeeded recently in designing hybrid charge storage systems such as lithium-ion capacitors (LICs) with the benefits of higher energy than supercapacitors and more power density than batteries. However, sluggish Li-ion diffusion of battery anode is one of the main barriers and hampers the development of high-performance LICs. Herein, is introduced a new conversion/displacement type anode, MnCO₃ , via effectively recycling spent Li-ion batteries cathodes for LICs applications. The MnCO₃  cuboids are regenerated from the spent LiMn₂ O₄  cathodes by organic acid lixiviation process, and hydrothermal treatment displays excellent reversibility of 535  mAh g^-1  after 50  cycles with a Coulombic efficiency of >99%. Later, LIC is assembled with the regenerated MnCO₃  cubes in pre-lithiated form (Mn⁰  + Li₂ CO₃ ) as anode and commercial activated carbon (AC) as the cathode, delivering a maximum energy density of 169.4 Wh kg^-1  at 25 °C with ultra-long durability of 15,000 cycles. Even at various atmospheres like -5 and 50 °C, this LIC can offer a energy densities of 53.8 and 119.5 Wh kg^-1 , respectively. Remarkably, the constructed AC/Mn⁰  + Li₂ CO₃ -based LIC exhibits a good cycling performance for a continuous 1000 cycles with >91% retention invariably for all temperature conditions.

An aqueous polyethylene oxide-based solid-state electrolyte with high voltage stability for dendrite-free lithium deposition via a self-healing electrostatic shield

Lithium metal batteries (LMBs) have attracted extensive attention for their ultrahigh energy density. However, the uncontrollable growth of Li-dendrites results in poor cyclability and potential safety risks, thus preventing their practical application. Herein, a flexible and cost-effective aqueous polyethylene oxide (PEO)-based solid-state electrolyte is prepared, which enables uniform and dendrite-free Li deposition by introducing Cs⁺ with an electrostatic shielding mechanism at high current densities. The self-assembly of PEO and bacterial cellulose by hydrogen bonding reduces the crystallinity of PEO and increases uniformly the distribution of lithium ions. With excellent flexibility and thermal stability, such a 3D polymer solid-state electrolyte exhibits an enhanced electrochemical stability window of 5.8 V versus Li/Li⁺ potential and a high ionic conductivity of 1.28 × 10^-4 S cm^-1 at 60 °C. The Li|BC-PEO-Cs⁺|Li symmetric cells operate stably for more than 1000 h. Furthermore, Li|BC-PEO-Cs⁺|LiFePO₄ (LFP) cells show remarkable enhancement in capacity (163.4 mA h g^-1 at 0.1 C), cycling stability (with a capacity retention of 96% after 500 cycles at 1 C) and high functionality and safety (withstanding folding and cutting) in practical applications.

Recycling Strategies for Ceramic All-Solid-State Batteries—Part I: Study on Possible Treatments in Contrast to Li-Ion Battery Recycling

In the coming years, the demand for safe electrical energy storage devices with high energy density will increase drastically due to the electrification of the transportation sector and the need for stationary storage for renewable energies. Advanced battery concepts like all-solid-state batteries (ASBs) are considered one of the most promising candidates for future energy storage technologies. They offer several advantages over conventional Lithium-Ion Batteries (LIBs), especially with regard to stability, safety, and energy density. Hardly any recycling studies have been conducted, yet, but such examinations will play an important role when considering raw materials supply, sustainability of battery systems, CO2 footprint, and general strive towards a circular economy. Although different methods for recycling LIBs are already available, the transferability to ASBs is not straightforward due to differences in used materials and fabrication technologies, even if the chemistry does not change (e.g., Li-intercalation cathodes). Challenges in terms of the ceramic nature of the cell components and thus the necessity for specific recycling strategies are investigated here for the first time. As a major result, a recycling route based on inert shredding, a subsequent thermal treatment, and a sorting step is suggested, and transferring the extracted black mass to a dedicated hydrometallurgical recycling process is proposed. The hydrometallurgical approach is split into two scenarios differing in terms of solubility of the ASB-battery components. Hence, developing a full recycling concept is reached by this study, which will be experimentally examined in future research.

A mini-review: emerging all-solid-state energy storage electrode materials for flexible devices

New technologies for future electronics such as personal healthcare devices and foldable smartphones require emerging developments in flexible energy storage devices as power sources. Besides the energy and power densities of energy devices, more attention should be paid to safety, reliability, and compatibility within highly integrated systems because they are almost in 24-hour real-time operation close to the human body. Thereupon, all-solid-state energy devices become the most promising candidates to meet these requirements. In this mini-review, the most recent research progress in all-solid-state flexible supercapacitors and batteries will be covered. The main focus of this mini-review is to summarize new materials development for all-solid-state flexible energy devices. The potential issues and perspectives regarding all-solid-state flexible energy device technologies will be highlighted.

Poly(vinylene carbonate)-Based Composite Polymer Electrolyte with Enhanced Interfacial Stability To Realize High-Performance Room-Temperature Solid-State Sodium Batteries

Solid-state rechargeable batteries using polymer electrolytes have been considered, which can avoid safety issues and enhance energy density. However, commercial application of the polymer electrolyte solid-state battery is still significantly limited by the low room-temperature ionic conductivity, poor mechanical properties, and weak interfacial compatibility between the electrolyte and electrode, especially for the room-temperature solid-state rechargeable battery. In this work, a poly(vinylene carbonate)-based composite polymer electrolyte (PVC-CPE) is reported for the first time to realize room-temperature solid-state sodium batteries with high performances. This in situ solidified PVC-CPE possesses superior ionic conductivity (0.12 mS cm^-1 at 25 °C), high Na⁺ transference number (t_Na⁺ = 0.60), as well as enhanced electrode/electrolyte interfacial stability. Notably, the composite cathode NaNi_1/3Fe_1/3Mn_1/3O₂ (c-NFM) is designed through the in situ growth of the polymer electrolyte inside the electrode to decrease interfacial resistance and facilitate effective ion transport in electrode/electrolyte interfaces. It is demonstrated that the solid-state c-NFM/PVC-CPE/Na battery assembled by a one-step in situ solidification method exhibits remarkably enhanced cell performances at room temperature compared with a reference NFM/PVC-CPE/Na assembled through a conventional ex situ method. The battery presents a high initial specific capacity of 104.2 mA h g^-1 at 0.2 C with a capacity retention of 86.8% over 250 cycles and ∼80.2 mA h g^-1 at 1 C. This study suggests that PVC-CPE is a very promising electrolyte for solid-state sodium batteries. This study also suggests a new method to design high-performance polymer electrolytes for other solid-state rechargeable batteries to realize high safety and considerable electrochemical performance at room temperature.

Low-temperature all-solid-state lithium-ion batteries based on a di-cross-linked starch solid electrolyte

The preparation of a low-temperature solid electrolyte is a challenge for the commercialization of the all-solid-state lithium-ion battery (ASSLIB). Here we report a starch-based solid electrolyte that displays phenomenal electrochemical properties below room temperature (RT). The starch host of the electrolyte is synthesized by two cross-linking reactions, which provide sufficient and orderly binding sites for the lithium salt to dissolve. At 25 °C, the solid electrolyte has exceptional ionic conductivity (σ, 3.10 × 10⁻⁴ S cm⁻¹), lithium-ion transfer number (t⁺, 0.82) and decomposition potential (dP, 4.91 V). At −20 °C, it still has outstanding σ (3.10 × 10⁻⁵ S cm⁻¹), t⁺ (0.72) and dP (5.50 V). The LiFePO₄ ASSLIB assembled with the electrolyte exhibits unique specific capacity and long cycling life below RT, and the LiNi_0.8Co_0.1Mn_0.1O₂ ASSLIB can operate at 4.3 V and 0 °C. This work provides a solution to solve the current challenges of ASSLIBs to widen their scope of applications.

The all-solid-state lithium battery based on di-cross-linked starch electrolyte is applicable at low temperature.