Failure modes of valve-regulated lead-acid batteries for electric bicycle applications in deep discharge

Multi-Walled Carbon Nanotubes Percolation Network Enhanced the Performance of Negative Electrode for Lead-Acid Battery

“…SO 4 2− + 2H + −→ H 2 SO 4 [3] If the above elementary processes are impeded, the charge process is impeded and certain quantities of PbSO 4 in the plates are not reduced to Pb. The accumulation of lead sulfate reduces markedly the effective surface-area and limits the performance.…”

Power and life enhancement of battery-electrical double layer capacitor for hybrid electric and charge-depleting plug-in vehicle applications

“…In the literature, different approaches can be found that describes the battery stress in function of a specific parameter such as temperature, capacity Table 4 Internal resistance of battery, EDLC and battery-EDLC based on data sheet [11,18]. and voltage [3,7,17,18]. However, the literature is deficient in the description of the impact of the high discharge rates to the lifetime of the battery equipped with EDLC's.…”

“…In addition, it is well documented [3,4] that the valve-regulated lead-acid (VRLA) battery fails prematurely due to the sulfation of the negative plates. The negative plates suffer from a progressive grow-up of hard lead sulfate (PbSO 4 ) on the surface which makes the battery harder to recharge and reduces the available capacity.…”

Effects of cyclic voltammetric scan rates, scan time, temperatures and carbon addition on sulphation of Pb disc electrodes in aqueous H2SO4

“…1,2 It was well documented that irreversible sulfation of lead negative electrode is the main reasons accounting for failure of lead-acid batteries. 3,4 Irreversible sulfation is defined as formation of non-soluble lead sulfate on lead negative electrodes with large particle sizes and high crystalline upon charge-discharge process and/or rest of lead-acid batteries. The generated lead sulfate is electrochemically inactive and can hardly be electrochemically transformed into lead upon following electrochemical polarizations.…”

“…The origins of such failure are mainly due to (1) uneven of electrode and therefore uneven distribution of electrolyte and electrical fields; (2) spontaneous formation of large PbSO 4 granules at the expense of dissolved small PbSO 4 granules under the circumstance of insufficient charging during normal operation and (3) excessively deep and/or slow discharge. 3,4 Addition of water and/or diluted electrolyte is the most straightforward protocol to restore degraded spent batteries. In the above physical restoration, the added water could facilitate dissolution of generated large PbSO 4 granules and supplement water consumed by water decomposition upon irreversible sulfation and therefore restrain irreversible sulfation of lead negative electrode.…”