Cycle Life Of Lead-acid Batteries Research Articles

Hybrid battery energy storage for light electric vehicle — From lab to real life operation tests

The aim of the research presented in the paper is to improve the lifetime of lead-acid battery systems which are widely used in low-speed electric vehicles or utility vehicles, since the cycle life of lead-acid batteries is nonlinearly dependent on the depth of discharge and electrolyte temperature. The solution proposed here is to connect lead-acid batteries with a small lithium‑iron-phosphate battery using only a diode. This connection is simple and does not require the use of an actively controlled converter. The concept was tested at various levels of an experiment, from the initial calculation of cycle life improvement and simulation, through a laboratory experiment, all the way to operational environment tests. The results obtained confirmed the main assumptions of the study: decrease in the depth of discharge of lead-acid battery for the distance traveled of around 17 %—which would translate into a 30 % better cycle life according to the characteristics indicated by the producers—and decrease in the root mean square and maximum current values of lead-acid battery by around 40–50 % and 26 %, respectively. Range extension was also achieved in vehicles. The solution has been successfully introduced to the market and is now used in few light electric vehicles.

N-doped reduced graphene oxide loading nano lead oxide as negative additive for enhanced properties of lead-carbon batteries

The use of carbon materials could significantly increase the cycle life of lead-acid batteries (LABs) by inhibiting the irreversible sulfation. However, it will exacerbate hydrogen evolution side reaction at the negative plates, which not only reduce coulombic efficiency, destroy the plate microstructure, but also accelerate moisture loss. Herein, a N-doped reduced graphene oxide/lead oxide nanoparticles(N-rGO/PbO) composite was synthesized by hydrothermal and calcination process. Comparative studies found that the strategy of loading with metal oxide nanoparticles, which with high hydrogen evolution overpotentials (ηH), and N-doped can retard the rate of hydrogen evolution reaction (HER) on composite materials. In addition, the resultant composite can help to promote the uniform distribution of graphene in negative active materials (NAM) and structural stability of the negative plate and enhance the combination between the additive and NAM. Thanks to the superiority of the prepared composite material additives, the high-rate partial-state-of-charge (HRPSoC) life of lead-carbon battery (LCB) containing the composite additive shown a prominent enhancement. Specifically, the simulated micro battery containing 0.50 wt% N-rGO/PbO additive showed the best cycle life (17390 cycles), compared to that with same content rGO additive (7742 cycles) and that without any carbon additive (2777 cycles). What’s more, by adding 0.50 wt% N-rGO/PbO additive, the initial discharge capacity of simulated micro battery could be enhanced from 145.6 to 162.6 mAh g−1 and the rate capability had also been improved. In summary, the N-rGO/PbO composite manifests great potential in lead-carbon batteries for improving HRPSoC cycle life and discharge capacity.

Using silkworm excrement and spent lead paste to prepare additives for improving the cycle life of lead-acid batteries

Sulfation at the negative electrode remains a crucial failure in lead-acid batteries. To overcome the sulfation issue, herein, a silkworm excrement-based porous carbon (SEPC) material has been successfully synthesized by a facile one-step metal catalytic cracking method. Consequently, SEPC and desulfurization spent lead paste were mixed and calcined to obtain a composite material of SEPC and PbO (SEPC-PbO), and employed as the negative additive to suppress the sulfation of lead-acid battery. The morphological characterization exhibits that SEPC has a plentifully mesoporous structure. The specific discharge capacity of the SEPC-PbO negative plate is 165 mAh g−1 (11.5% higher than the negative plate of traditional lead-acid battery) and ensuring remarkable suppression of hydrogen evolution. After 400 100% depth of discharge (DOD) cycles, the capacity retention rate is still as high as 84% and after 3000 5%DOD cycles, the active substances of the SEPC cell remained high reversible. In addition, the development of new lead-acid batteries, the synthesis of biochar materials, and the combination of waste lead paste recycling industries were explored. All these contribute to the decrease of the pollution risk of the silkworm breeding and lead-acid battery recovery industry and revolutionize the sustainable utilization of carbon resources.

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.

What are the tradeoffs between battery energy storage cycle life and calendar life in the energy arbitrage application?

This paper develops a method and framework for analyzing the tradeoffs between the calendar life and cycle life of battery energy storage used for energy arbitrage in a wholesale electricity market. We implement a linear program to analyze the revenue potential of a battery system participating in the Electric Reliability Council of Texas (ERCOT) electricity market during 2002–2015, and show how the number of charge-discharge cycles performed in a year affects annual revenue potential. Then, we calculate the potential present worth (or the sum of discounted yearly revenues) of battery systems of various discharge durations and roundtrip efficiencies as a function of their calendar life and cycle life, and show how increasing calendar life and cycle life affects present worth. We show that increasing calendar life provides a greater benefit than increasing cycle life for lithium-ion, sodium-sulfur, and vanadium-redox flow batteries, which counters conventional notions about the importance of battery cycle life. However, we find that increasing the cycle life of lead-acid batteries provides a greater benefit than increasing calendar life, because lead-acid batteries have a lower cycle life than other technologies.

Graphene nanosheets as backbones to build a 3D conductive network for negative active materials of lead–acid batteries

Graphene nanosheets (GNs) with large specific surface area, high conductivity, and excellent flexibility were integrated with negative active materials (NAM) as backbones to construct a continuous conductive network to suppress the sulfation of negative plates and improve the cycle-life of lead–acid batteries (LABs) under high-rate partial state-of-charge (HRPSoC) condition. The microstructure of GNs was characterized by scanning electron microscopy (SEM), nitrogen adsorption–desorption techniques, fourier transform infrared (FTIR), and Raman spectroscopy. The effect of GNs at different contents in the electrochemical performances of negative plates and LABs is investigated. The electrochemical tests show that the cycle-life of LABs under HRPSoC conditions has improved by more than 370% and the utilization ratio of NAM has been raised to 63.7%, when 0.9 wt% additions of GNs was added to NAM. It is found that the GNs will be a promising carbonaceous additive for long cycle-life of LABs under HRPSoC conditions.

Enhancing the cycle life of Lead-Acid batteries by modifying negative grid surface

Because of their commercial acceptability, Lead-Acid batteries are of significant importance, thus researchers constantly attempt to find new approaches to enhance their efficiency. In the present study, I sought to modify surface of the negative grids with aniline in sulfuric acid solution. Then, the modified grids were used as current collectors in negative plates of the cells in Lead-Acid batteries. The XRD, SEM, XPS, chronopotentiometry and cyclic voltammetry were employed for characterization of the modified grids, and constant current charge/discharge and electrochemical impedance spectroscopy techniques were used for studying the performance of the Lead-Acid cells. The results indicate that the growth of polyaniline fractal modifies the distance between the collector grids and active materials and the process of PbSO4 reduction to the metallic lead is enhanced on the modified lead grid. Although modification of the collector grids in negative plate seems to have no significant effect on the initial capacity of the cells, the grids modified with a 5mM aniline solution shows a higher cumulative capacity after 90 complete charge/discharge cycles. XRD analysis on the negative active materials revealed a decrease in accumulation of the lead sulfate crystals on the negative plate. So, taking the decay in capacity to 35% of the initial amount as a criterion, cycle life of cells increased from 35 in the cells with commercial plates to >100 in the cells of the modified grids. Such a modification with three folds increment in battery life would help the Lead-Acid batteries to compete in the modern world.

Improving the cycle life of lead-acid batteries using three-dimensional reduced graphene oxide under the high-rate partial-state-of-charge condition

Abstract A three-dimensional reduced graphene oxide (3D-RGO) material has been successfully prepared by a facile hydrothermal method and is employed as the negative additive to curb the sulfation of lead-acid battery. When added with 1.0 wt% 3D-RGO, the initial discharge capacity (0.05 C, 185.36 mAh g −1 ) delivered by the battery is 14.46% higher than that of the control cell (161.94 mAh g −1 ); and the cycle life under the high-rate partial-state-of-charge (HRPSoC) condition is significantly improved by more than 224% from 8142 to 26,425 cycles. In comparison to the conventional carbon additions like the activated carbon and acetylene black, the 3D-RGO also exhibits the highest initial discharge capacity, the best rate capabilities and the longest HRPSoC cycling life. Finally, we propose a possible mechanism for 3D-RGO to suppress lead-acid battery sulfation, where the abundant pore structure and excellent conductivity of 3D-RGO may have a synergistic effect on facilitating the charge and discharge process of negative plate.

Balancing for Lead-Acid Batteries of Electric Motorcycles

For high-power applications such as electric motorcycles, batteries in series to provide the required voltage is fairly common. The 48V is 12V connected four cells in series for lead-acid batteries of electric motorcycles. After charging and discharging of lead-acid batteries several times, the voltages are often imbalance. Without proper protection, may cause an excessive discharge of lead-acid batteries for early damage. Therefore, lead-acid battery module requires a simple balance circuit to improve battery life in order to avoid over-voltage or under-voltage condition occurs. Energy balance circuit to improve lead-acid battery module matching problems, make the safety and cycle life of lead-acid batteries to improve. This research intends to complete balanced circuit design of lead-acid batteries.

The Improving Measures Research on the Cycle Life of Lead-Acid Batteries for Electric Vehicles

By describing the main affecting factors of the small electric vehicles cycle life for the lead-acid batteries,then studying the main technical measures that how to improve the deep cycle performance of the batteries to prolong its life.When the methods of the combination of grid alloys ,mixing paste and curing process parameters control, the selection of the negative organic additives and the sets mode of the positive and negative plates were used,the battery performance and the cycle life greatly improved and the failure rate decreased.

Extending cycle life of lead-acid batteries: a new separation system allows the application of pressure on the plate group

Since 1983, it has been claimed that pressure applied on a lead-acid battery increases its cycle life. But until now, the use of pressure in production batteries was limited by the mechanical properties of the conventional separation systems (absorptive glass mat (AGM), and gel) which cannot withstand mechanical pressure. In 1997, Daramic developed the new acid jellying separator (AJS) with the aim of combining the advantages of both conventional separation systems and to allow the application of lasting plate group pressure. The new separation system was evaluated and much information was gained on the effect of pressure in a lead-acid battery, e.g. on the evolution of the mechanical pressure during one cycle and during cycle life.

Effect of compression on the behaviour of lead-acid batteries

Mechanical pressure applied to the plate group is known to increase the cycle life of lead-acid batteries. However, the mechanism of the active material stabilisation process is not completely understood yet. The evolution of mechanical pressure in a lead-acid battery during a cycle and through cycle life is also a topic with still many open questions. Additionally, the separation systems available today are not able to exert high compression on the electrode plates: glass mats crush when compressed too much and the gel design does not allow any significant pressure generation at all. Daramic have developed the new acid jellying separator (AJS) allowing the application of mechanical pressure on the plate group. This paper reports on 1. The capacity evolution during cycling for cells with different separation systems namely AGM, gel and AJS, under a variety of initial compression levels. 2. The evolution of mechanical pressure on the cell walls during a cycle and through cycle life for different separation systems, and initial compression levels. 3. The condition of the active materials at the end of life for cells cycled under compression. 4. The effect of the addition of phosphoric acid to the electrolyte. 5. The effect of the application of mechanical pressure on the corrosion of pure lead based on cyclic voltammetry measurements under compression. The results of these studies are presented together with some conclusions about the mechanism and effect of compression on a VRLA battery.

Structure of PbSb 2O 6 and its relationship to the crystal chemistry of PbO 2 in antimonial lead-acid batteries

The crystal structure of PbSb 2O 6, space group P 31m, a = 5.3006(1), c = 5.3792(1) , Å, V = 130.89(2), Å 3, Z = 1, D x = 6.936 g cm −3, has been refined at 295 K by Rietveld analysis of step-scan neutron powder diffraction data (λ = 1.500 Å, μ = 0.179 cm −1): R wp = 0.0614 for 2898 step intensities, R B = 0.0141 for 150 reflections. The structure consists of gibbsitelike sheets of edge-sharing SbO 6 octahedra oriented perpendicular to the c-axis. These sheets alternate with layers of isolated PbO 6 octahedra positioned above and below the vacant sites in the adjacent (Sb 2O 6) 2− layers. The SbO 6 octahedra have symmetry 32 and a bond length of 1.9904(4) Å; the PbO 6 octahedra have symmetry 3m and a bond length of 2.5633(6) Å. The properties of this structure and its relationship to the polymorphs of PbO 2 provide possible explanations for the well-known beneficial effect of antimony on the cycle life of lead-acid batteries.