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US-20260128387-A1 - LEAD-ACID BATTERY AND MANUFACTURE METHOD

US20260128387A1US 20260128387 A1US20260128387 A1US 20260128387A1US-20260128387-A1

Abstract

Lead-acid batteries or cells, electrodes and bipolar plates for the same, and methods of manufacturing the same are provided. The lead acid batteries comprise a positive and/or negative electrode having a specific pore size diameter distribution. The pore size diameter distribution may comprise: a ratio of a volume of pores having a pore size diameter greater than 20 μm to a total pore volume of at least 15%; or a volume of pores having a pore size diameter greater than 20 μm of at least 0.020 ml/g.

Inventors

  • Stuart McKenzie
  • Shane Christie

Assignees

  • ARCACTIVE LIMITED

Dates

Publication Date
20260507
Application Date
20230825
Priority Date
20220830

Claims (20)

  1. 1 . A lead-acid battery or cell, wherein the battery or cell is a non-gel lead-acid battery or cell or absorptive glass mat (AGM) lead-acid battery or cell, comprising: a positive electrode comprising a positive active material (PAM); a negative electrode comprising a negative active material (NAM); and a separator capable of immobilising an electrolyte disposed between the positive and negative electrodes, the positive electrode and negative electrode each having a pore size diameter distribution measured by mercury porosimetry, wherein the pore size diameter distribution of the positive and/or negative electrode comprises a ratio of a volume of pores having a pore size diameter greater than 20 μm to a total pore volume of at least 15%.
  2. 2 . The lead-acid battery or cell of claim 1 , wherein the pore size diameter distribution of the positive and/or negative electrode comprises a volume of pores having a pore size diameter greater than 20 μm of at least 0.020 ml/g.
  3. 3 . The lead-acid battery or cell of claim 1 , wherein the negative electrode has said pore size diameter distribution, or both the negative and positive electrode have said pore size diameter distribution.
  4. 4 . The lead-acid battery or cell of claim 1 , wherein the battery or cell is an absorptive glass mat (AGM) battery and/or is a bipolar lead-acid battery.
  5. 5 . (canceled)
  6. 6 . The lead-acid battery or cell of claim 1 , wherein the separator has a pore size diameter distribution measured by capillary flow porometry, wherein the pore size diameter distribution of the positive and/or negative electrode comprises a ratio of the volume of pores greater than the mode pore size diameter of the separator to the total pore volume of at least 80% or 85%.
  7. 7 . The lead-acid battery or cell of claim 1 , wherein the separator has a pore size diameter distribution measured by capillary flow porometry, wherein the separator has a mode pore size diameter less than or equal to about 20 μm, 18 μm, 16 μm, 15 μm, 14 μm, 13 μm, 12 μm, 11 μm, 10 μm, 9 μm, 8 μm, 7 μm, 6 μm, 5 μm, 4 μm, 3 μm, 2 μm, or 1 μm.
  8. 8 . The lead-acid battery or cell of claim 1 , wherein the positive and/or negative electrode are formed from a paste which at impregnation has a density of from about 1.5 to 5 or from about 1.5 to 5.5 g/cm 3 .
  9. 9 . An electrode for a lead-acid battery or cell comprising an active material and having a pore size diameter distribution measured by mercury porosimetry, wherein the pore size diameter distribution comprises a ratio of a volume of pores having a pore size diameter greater than 20 μm to a total pore volume of at least 15%.
  10. 10 . The electrode of claim 9 , wherein the pore size diameter distribution of the electrode comprises a volume of pores having a pore size diameter greater than 20 μm of at least 0.020 ml/g.
  11. 11 . The lead-acid battery or cell or electrode of claim 1 , wherein the pore size diameter distribution of the positive and/or negative electrode comprises a ratio of a volume of pores having a pore size diameter greater than 10 μm to a total pore volume of at least 50%, 55%, 60%, 65%, or 70%.
  12. 12 . The lead-acid battery or cell of claim 1 , wherein the pore size diameter distribution of the positive and/or negative electrode comprises a volume of pores having a pore size diameter greater than 10 μm of at least 0.070, 0.075, 0.080, 0.085, 0.090, 0.095, 0.100, 0.110, or 0.120 ml/g.
  13. 13 . (canceled)
  14. 14 . (canceled)
  15. 15 . (canceled)
  16. 16 . (canceled)
  17. 17 . (canceled)
  18. 18 . (canceled)
  19. 19 . The lead-acid battery or cell of claim 1 , wherein the pore size diameter distribution of the electrode er of the positive and/or negative electrode comprises a ratio of a volume of pores having a pore size diameter greater than 35 μm to a total pore volume of at least 10%, 15%, or 20%.
  20. 20 . The lead-acid battery or cell of claim 1 , wherein the pore size diameter distribution of the positive and/or negative electrode comprises a volume of pores having a pore size diameter greater than 35 μm of at least 0.010, 0.015, 0.020, 0.025, or 0.030 ml/g.

Description

RELATED APPLICATIONS This application is a national stage application under 35 U.S.C. 371 for International Application No. PCT/IB2023/058428, filed on Aug. 25, 2023, which claims the benefit of priority of New Zealand Application No. 791937, filed on Aug. 30, 2022, the entire contents of which applications are incorporated herein by reference. FIELD OF THE INVENTION The invention relates to lead-acid batteries or cells, electrodes and bipolar plates for the same, and methods of manufacturing the same. BACKGROUND The decarbonisation of electricity generation is expected to expand the market for batteries. A significant factor in the competitiveness of a battery solution is the cost of the discharged electricity, known as the Levelized Cost of Storage (LCOS). The LCoS of a battery is essentially the net present value (NPV) of all costs associated with installation and operation of the battery (for example, the battery, control equipment, power conversion equipment, housing, cabling etc.) divided by the lifetime energy (kWh) discharged from the battery. Lead-acid batteries (LABs) have a number of advantages compared to other storage technologies, such as Li-ion batteries, in that they are recyclable, are generally safe and are fundamentally low-cost batteries to produce. However, due to the lower amount of energy throughput over the life of the battery, lead-acid batteries have higher (and thus less attractive) LCOS metrics than Li-ion batteries. A typical absorptive glass mat (AGM) lead-acid battery might achieve 200-500 capacity turnovers before reaching the end of its life, whereas Li-ion can achieve say 2,000 capacity turnovers. A battery is generally considered to have reached the end of its life when it is no longer able to meet the design requirements for the application. For energy storage system (ESS) applications, battery end of life for lead-acid batteries is commonly expressed as having been reached when the discharged capacity is some fraction (for example, 50%) of its initial capacity. ESS batteries are typically valve regulated lead-acid (VRLA) batteries. In VRLA batteries the electrolyte is immobilized (in contrast to flooded batteries) to reduce electrolyte stratification which degrades and reduces the life of the battery. There are two types of immobilised electrolyte VLRAs: AGM batteries and gel batteries. AGM batteries include an absorptive glass mat as a separator disposed between the positive and negative electrodes. The glass mat comprises a network of glass fibres of different sizes, typically ranging from about 1 to about 4 mm in length and about 0.5 to about 3 μm in diameter, typically less than about 1 μm in diameter. The mixture of different fibre sizes is to balance competing requirements of electrolyte entrainment, fabric compressibility and incompressibility, and ability to be filled. The fibres entrain the electrolyte due to the high surface tension between the electrolyte and fibres, thus immobilising the electrolyte. Battery manufacturers target separator saturation levels that are high, but not fully saturated, which provide gas channels for O2 gas produced at the positive electrode to diffuse across the separator and recombine to water at the negative electrode. This reduces water loss from the battery, increasing the turnover capacity of the battery. Gel batteries include a gelling agent, such as SiO2 nano powder, which forms a gel that immobilises the electrolyte, helping to prevent, for example stratification, or electrolyte spillage if the battery is tipped on its side, and acts as a separator. Very fine cracks that form in the gel provide gas channels for O2 diffusion. Gel batteries typically achieve significantly higher turnover capacity than AGM batteries. Whereas an AGM battery might achieve 200-500 100% depth of discharge (DoD) cycles, a gel battery might achieve 1,500 cycles. There are, however, drawbacks to gel batteries. One is that the high internal resistance of the gel separator means that gel batteries are only suitable for certain niche applications. An important failure mode for VRLA batteries is a phenomenon known as “dry out”. Dry out occurs when the saturation level of the separator drops. This occurs due to an inevitable side reaction that occurs during charging-hydrolysis. While the O2 that is formed during hydrolysis is typically recombined at the negative electrode, any H2 that is produced is lost from the battery (due to very low H2 to water conversion), along with a stoichiometric amount of O2, meaning that water is slowly lost from the battery. There is a need for lead-acid batteries with increased capacity turnover and/or reduced water loss. It is an object of the present invention to go some way to meeting this need; and/or to at least provide the public with a useful choice. In this specification where reference has been made to patent specifications, other external documents, or other sources of information, this is generally for the purpose