US 12,113,178 B2
Separators, batteries, battery strings with improved performance, and related methods
Eric H. Miller, Philpot, KY (US); and Yanxia Wu, Shanghai (CN)
Assigned to Daramic, LLC, Charlotte, NC (US)
Filed by Daramic, LLC, Charlotte, NC (US)
Filed on Aug. 10, 2016, as Appl. No. 15/232,898.
Claims priority of provisional application 62/203,050, filed on Aug. 10, 2015.
Prior Publication US 2017/0054123 A1, Feb. 23, 2017
Int. Cl. H01M 10/12 (2006.01); H01M 50/417 (2021.01); H01M 50/437 (2021.01); H01M 50/44 (2021.01); H01M 50/454 (2021.01); H01M 50/463 (2021.01); H01M 10/14 (2006.01)
CPC H01M 10/121 (2013.01) [H01M 50/417 (2021.01); H01M 50/437 (2021.01); H01M 50/44 (2021.01); H01M 50/454 (2021.01); H01M 50/463 (2021.01); H01M 10/14 (2013.01); H01M 2220/10 (2013.01); H01M 2220/20 (2013.01); Y02E 60/10 (2013.01); Y02P 70/50 (2015.11); Y02T 10/70 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A battery string comprising:
four or more monoblock valve regulated lead-acid (VRLA) batteries wired in series, wherein a total voltage of the battery string is 48 volts or greater;
each VRLA monoblock battery comprises
an alternating sequence of positive and negative electrodes, and
a separator disposed between each of the positive and negative electrodes, the separator consists of a microporous polyolefin layer including a surfactant sandwiched between a first absorptive glass mat and a second absorptive glass mat, wherein the first absorptive glass mat has a thickness from 1.0 to 3.3 mm and the second absorptive glass mat has a thickness of 0.6 mm, wherein the microporous polyolefin layer is a polyethylene layer with a ribbed or embossed backweb, a backweb thickness of the microporous polyolefin layer not including the thickness of the ribs or embossments is from 0.05 mm to 0.25 mm, and the microporous polyolefin layer with the ribbed or embossed backweb of the separator has a bi-modal pore size distribution consisting of a first region of pores consisting of larger pores having a size of 1 to 6 microns and a second region of pores consisting of smaller pores having a size of less than 0.9 micron, wherein 90% of the pores are smaller pores.