概括单体蓄电池充放电的平均寿命

概括单体蓄电池充放电的平均寿命 鉴于相同原材料、同批次的单体电池,容量、内阻、寿 命等性能参数符合正态分布并且离散程度有限;鉴于在 相同的电流激励条件下,单体电池电压变化过程的一致 性渐进逼近其它性能参数的一致性,其中最重要的参数 是荷电程度;鉴于电池在未曾历经过过充、过放的损害, 在其生命期里不容易提前失效,可以推断,如果在充放 电过程中通过能量变换的办法实施电池组中单体电压 的均衡控制,使单体电压趋于一致,以单体电池为动力 源如移动通讯,电源管理技术已经十分完善,但在蓄电 池组中,单体之间的差异总是存在的,以容量为例,其差 异性永不会趋于消失,而是逐步恶化的。组中流过同样 电流,相对而言,容量大者总是处于小电流浅充浅放、趋 于容量衰减缓慢、寿命延长,而容量小者总是处于大电 流过充过放、趋于容量衰减加快、寿命缩短,两者之间 性能参数差异越来越大,形成正反馈特性,小容量提前 失效,组寿命缩短。 As raw materials, with the same batch of monomer battery, the capacity, internal resistance, service life and other performance parameters conform to normal distribution and discrete degree is limited; Given under the condition of same current incentive, of monomer battery voltage change process consistency, gradually approaching other performance parameters of the degree of one of the most important parameter is the charged; Light never after have the charger and a battery damage, in its lifetime is not easy to early failure, can be concluded that if in the process of charging and discharging through the way of energy conversion implementation of monomer in the battery pack voltage balancing control, lead to the agreement monomer voltage, monomer battery as power source, such as mobile communications, power management technology has been very perfect, but in the battery, always exist differences between monomer, capacity, for example, the differences will never tend to disappear, but gradually deteriorating. Group through the same current, in contrast, capacity is always in small current shallow fill light put, capacity of slow attenuation, longevity, and small breasts are large current charge discharge capacity, capacity attenuation speed, shorten the service life, performance parameters of the differences between the two is more and more big, the formation of the positive feedback features, small capacity failure ahead of time, group shortened lifespan. 2、蓄电池组的充电过程 2, the battery charging process 2.1、充电 2.1, charging 目前充电主要是限压限流法,初期恒流(cc)充电, 电池接受能力最强,主要为吸热反应,但温度过低时,材 料活性降低,可能提前进入恒流阶段,因此在北方冬天 低温时,充电前把电池预热可以改善充电效果。随着充 电过程不断进行,极化作用加强,温升加剧,伴随析气, 电极过电位增高,电压上升,当荷电达到约70~80%时,电 压达到最高充电限制电压,转入恒压(cv)阶段。理论上 并不存在客观的过充电压阈值,若理解为析气、升温就 意味着过充,则在恒流阶段末期总是发生不同程度的过 充,温升达到40~50摄氏度,壳体形变容易感测,部分逸 出气体还可以复合,另一些就作为不可逆反应的结果, 损失了容量,这可以看作电流强度超出电池接受能力。 在恒压阶段,有称涓流充电,大约花费30%的时间充入 10%的电量,电流强度减小,析气、温升不再增加,并反方 向变化。 Charging at present is mainly pressure limiting current limit method, the initial constant current (cc) charging, the battery to accept ability is strongest, mainly for the endothermic reaction, but the temperature is too low, material activity decreased, may be in advance into the constant current phase, so cold in winter in the north, the battery before charging preheat improves the charging effect. With constant charging process, the polarization effect strengthen, temperature rise, along with gas chromatography, electrode overpotential increases, the voltage rise, when charged to about 70 ~ 80%, reached the highest voltage limiting voltage, charging into constant voltage (CV) phase. In theory there is no objective of charging voltage threshold, if understood as analysis, gas heating means overcharge, the end always happen during the constant current phase varying degrees of overcharge, 40 ~ 50 degrees Celsius temperature, sensor shell deformation easily, part of the escaping gas can also be compound, the other is as a result of irreversible reaction, loss of capacity, it can be seen as current strength than battery capacities. At constant pressure stage, has said a trickle charge, the cost about 30% into 10% of the time, current intensity decreases, gas analysis, temperature no longer increases, and changes in the opposite direction. 2.2过充电 2.2 after charging 上述过程考虑电池组总电压或平均电压控制,其实 总有单体电压较高者,相对组内其它电池已经进入过充 电阶段。过充电时,若在恒流阶段发生,由于电流强度大, 电压、温升、内压持续升高,若继续过充,气阀打开、温 升继续升高、不可逆反应加剧。恒压阶段,电流强度较 小,过充症状不如恒流阶段显著。酿酒设备只要温升、 内压过高,就伴随副反应,电池容量就会减少,而副反应 具有惯性, 发展 到一定程度,可能在充电中也可能在 充电结束后的短时间里使电池内部物质燃烧,导致电池 报废。过充电加速电池容量衰减、导致电池失效,百害 而无一利。 Considering above average total battery voltage or voltage control, actually there is always a monomer voltage high, relative to other cells in the group has entered the stage of charging. Before charging, except in the constant current phase, due to the current intensity, voltage, temperature, inner pressure continued to rise, if continue to overcharge, the valve opens, and irreversible reaction temperature continues to rise. Constant pressure stage, the current strength is small, overcharge symptoms than constant current phase is remarkable. As long as the temperature rise, high internal pressure, is associated with side effects, battery capacity will be reduced, and the adverse event has inertia, development to a certain extent, may in charge may also be in charge of the battery in a short time after the matter inside burning, lead to dead batteries. Charging speed battery capacity attenuation, lead to battery failure, vile indeed. 3、蓄电池组的放电过程 3, the battery discharge process 3.1放电 3.1 discharge 导线电阻和触点电阻,电压继续下降,经过一段时 间以后,到达新的电化学平衡,进入放电平台期,电压变 化不明显,放热反应加电阻释热使电池温升较高。放电 电压曲线近似单体放电曲线,持续放电,电压曲线进入 马尾下降阶段,极化阻抗增大,输出效率降低,热耗增大, 接近终止电压时停止放电。 Wire resistance and contact resistance, voltage continues to fall, after a period of time, reach new electrochemical balance, into the discharge plateau, voltage change is not obvious, the exothermic reaction and resistance heat release the battery temperature rise is higher. Discharge voltage curve approximation monomer discharge curve, continue to discharge, the voltage curve into horsetail decline phase, polarization impedance increases, the output efficiency is reduced, heat consumption increases, close to the end stop discharge voltage. 3.2 过放电 3.2 after discharge 考虑组内单体电池,必有相对的过放电情况。在放 电后期,电压接近马尾曲线,组中单体容量正态分布,电 压分布很复杂,容量最小的单体电压跌落得也就最早、 最快,若这时其它电池电压降低不是很明显,小容量单 体电压跌落情况被掩盖,已经被过度放电。 Consider single cells in the group, there will be a turn had relative discharge condition. Late in the discharge, the voltage is close to mawei curve, single capacity of normal distribution, the voltage distribution is complex, the smallest capacity monomer voltage sags are the earliest, the fastest, if the battery voltage is lower when the other is not very obvious, monomer voltage drop were hide small capacity, has been excessive discharge. 观察单体过放情况,进入马尾曲线以后,若电流持 续较大,电压迅速降低,并很快反向,这时电池被反方向 充电,或称被动放电,活性物质结构被破坏,另一种副反 应很快发生,过一段时间,电池活性材料接近全部丧失, 等效为一个无源电阻,电压为负值,数值上等于反充电 流在等效电阻上产生的压降,停止放电后,原电池电动 势消失,电压不能恢复,因此,一次反充电足以使电池报 废。 Observe monomer through put, to enter after horsetail curve, if continued large current, the voltage decrease rapidly, and quickly reversed, the opposite direction of the battery is charging, discharge or passive, active material structure is broken, another side effects happen quickly, over a period of time, battery loss of active material is close to full, equivalent to a passive resistance, voltage is negative, the value is equal to reverse charge flow on equivalent resistance of pressure drop and stop after discharge, battery electromotive force disappears, the voltage can't recovery, therefore, a reverse charge enough to make a battery scrap. 4、先进的电池组使用方法 4, advanced battery usage 过充过放对电池的损害都是致命的,不同之处仅在 于过充产生大量气体、易自燃和爆炸、中药热敷减肥表 象剧烈,过放外观变化和缓、但失效速度却极快,在正常 使用中都应严格避免出现。 Put the damage to the battery overcharge too is fatal, the difference only lies in the overcharge to produce a large number of gas, easy spontaneous combustion and explosion, representation, discharge appearance change is gentle, but the failure rate is very fast, in normal use should be strictly avoided. 那么单体的相对荷电程度也趋于一致,可以实现同时 充足电、也同时放空电,进而,电池组的寿命应接近于单 体电池的平均寿命。 The degree of relative charged monomers, tend to be consistent, can achieve sufficient electricity, at the same time also empty electricity at the same time, in turn, the life of the battery pack can approximate to monomer average life expectancy of the battery.