Acid-treated multi-walled carbon nanotubes as additives for negative active materials to improve high-rate-partial-state-of-charge cycle-life of lead-acid batteries

In this work, a trace amount of acid-treated multi-walled carbon nanotubes (a-MWCNTs) is introduced into the negative active materials (NAMs) of a lead acid battery (LAB) by simply dispersing a-MWCNTs in the water, which is then added into the dry mixture of lead oxide powder, expanders and carbon black for lead paste preparation. The abundant oxygen-containing groups on the a-MWCNTs show significant influence on the chemical reactions happening during the curing process, leading to the improved properties of NAMs. Specifically, after formation, the NAMs containing 100 ppm a-MWCNTs display a spongy-like structure comprised of interconnected domino-like Pb slices, giving favorable porosity and electroactive surface area of the NAMs. Moreover, the quasi-rod structure of Pb slices provides the channels for fast electron transfer. These two features greatly accelerate the electrochemical reaction between Pb and PbSO₄, and hence hinder the accumulation of PbSO₄ crystals. As a result, the high-rate partial-state-of-charge (HRPSoC) cycle-life of the simulated cell constructed from the a-MWCNTs-containing negative plate achieves a HRPSoC cycle-life more than 1.5 times longer than the cell constructed when the negative plate contains only carbon black. Since our method is of great convenience and low-cost, it is expected to have a great feasibility in the LAB industry.

100 ppm aMWCNTs were incorporated into the NAMs of LABs. The oxygen-containing groups on the aMWCNTs induced the formation of interconnected domino-like Pb slices in the NAMs. Thus, the HRPSoC cycle-life of the simulated cell was improved by 50%.

Dynamic charge acceptance and hydrogen evolution of a new MXene additive in advanced lead-acid batteriesviaa rapid screening three-electrode method

A three-electrode system was developed to rapidly screen additives such as MXene through dynamic charge acceptance in lead-acid batteries.

Single-Wall Carbon Nanotube Doping in Lead-Acid Batteries: A New Horizon

The addition of single-wall carbon nanotubes (SWCNT) to lead-acid battery electrodes is the most efficient suppresser of uncontrolled sulfation processes. Due to the cost of SWCNT, we studied the optimization loading of SWCNT in lead-acid battery electrodes. We optimized the SWCNT loading concentrations in both the positive and negative plates, separately. Loadings of 0.01% and 0.001% in the positive and negative active masses were studied, respectively. Two volts of lead-acid laboratory cells with sulfuric acid, containing silica gel-type electrolytes, were cycled in a 25% and 50% depth-of-discharge (DOD) cycling with a charging rate of C and 2C, respectively, and discharge rates of C/2 and C, respectively. All tests successfully demonstrated an excellent service life up to about 1700 and 1400 cycles for 25% and 50% DOD operations, respectively, at a low loading level of SWCNT. This performance was compared with CNT-free cells and cells with a multiwall carbon nanotube (MWCNT) additive. The outstanding performance of the lead-acid cells with the SWCNT additive is due to the oxidative stability of the positive plates during charging and the efficient reduction in sulfation in both plates while forming conducting active-material matrices.

Study of cetyltrimethyl ammonium bromide and benzylideneacetone as electrolyte additives for valve-regulated lead-acid batteries under high-rate partial-state-of-charge conditions

Cetyltrimethyl ammonium bromide and benzylideneacetone can decrease the evolution rate of hydrogen and prolong the cycle life of VRLA batteries.

Effect of boron–carbon–nitride as a negative additive for lead acid batteries operating under high-rate partial-state-of-charge conditions

For BCN-NAM, under HRPSoC cycling conditions, the dominating elementary process is the formation of PbO instead of PbSO₄.

Enhanced electrochemical performance of a lead–acid battery by a surface modified negative grid with multiwall carbon nanotube coating

High-performance lead–acid battery (LAB) negative grids have been prepared using a simple carbon nanotube (CNT) coating method.

Enhanced cycle life of lead-acid battery using graphene as a sulfation suppression additive in negative active material

The addition of graphene to negative active materials of lead-acid batteries for sulfation suppression and cycle-life extension is reported. Proposed mechanistic model demonstrates the evolution of PbSO₄ surface coverage as cycle number increases.