EPS are equipped with forced-start, and this feature is forced to start over when the battery discharge without protection, you can go on unlimited discharge, So that depth, poor performance of the battery discharge may be due to EPS of this feature to start off on the damage it can not be reused. Nickel-metal hydride, nickel cadmium type battery has excellent deep discharge performance but the price is too expensive so it is not applicable The general lead-calcium-type lead-acid battery deep discharge capacity is relatively poor, and the UPS application of the minimum termination voltage is 9.5V, typically 10.2 - 10.5V or so, If deep-discharge batteries too deep can easily cause damage, but the market is still the basic EPS of the batteries with this, which is derived from the use of UPS battery habits, The reason is that EPS designers does not take into account the impact of EPS mandatory start on batteries or on lead-calcium-type and on lead-acid batteries and they also do not understand the depth of poor discharge capacity of this battery. In contrast only low-antimony (1-3%) of lead-antimony lead-acid battery is economical and have a strong depth of discharge performance and meets all the requirements of sealed maintenance ,which issuitable for EPS industry use, however, that such batteries also have a weakness of relatively higher self-discharge.The market currently has no such batteries used in EPS configuration.