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Reasons leading to short battery life
Dec 09, 2016

The first reason: the battery itself

Why do you say that! In the first phase we know the working principle of lead-acid batteries, lead-acid battery charging and discharging process is an electrochemical reaction processes, charge, the lead sulfate to form lead oxide, restore the discharge of lead oxide and lead sulfate. And sulfuric acid lead is a very easy crystal of material, dang battery in the electrolytic solution of sulfuric acid lead concentration high or static idle time had long Shi, on will "hold into" mission, formed small Crystal, these small Crystal again attract around of sulfuric acid lead, on as snowball as formed big of inert Crystal, Crystal Hou of sulfuric acid lead charging Shi not only cannot again restore into oxidation lead, also will precipitation attached in electrode Board Shang, caused has electrode Board work area declined, this a phenomenon called sulfide.

The second reason: causes of battery production

Particularity of lead-acid batteries for electric bicycles and battery manufacturers to take a variety of approaches. The most typical method is as follows:

① increasing the number plate. Table 5 6 the original design of the system to 6 tablets 7 tablet, 7 8, 9 or even 8 tablets. Reduced thickness of thin plates and separators, increasing the number of plates to increase the battery capacity.

② increasing share of sulfuric acid in batteries. Float pool share of sulphuric acid were generally between 1.21~1.28, and the share of sulfuric acid in batteries of electric bicycles are generally at about 1.36~1.38, so you can provide more current, improving the initial capacity of the battery.

③ increasing the amount and proportion of lead oxide positive electrode active material.

II there is a group of assembled cold solder joint problem. Prone to cold solder joint is plates. Each cell of the table with 15 plates was 15 solder, a battery 6 cells, there are 90 solder, a battery made up of 3 12V batteries, there are 270 solder.

The third reason: electric vehicle using the environment itself causes

As long as the lead-acid batteries, used in curing process of, other than lead-acid batteries in the field of used lead-acid battery for electric bicycle has a longer life, it is the lead-acid battery for electric bicycle has a working environment easier curing.

① deep discharge

Lead-acid batteries used in automobiles only one-way discharge at ignition, ignition generator will automatically charge the battery, no battery deep discharge. Electric bicycle riding can not charge, often over 60% deep discharge deep discharge, lead sulfate concentration, curing will be quite serious.

② high discharge current

General Electric 20 km cruise current is 4 a, this value is already higher than other areas of battery current, overload and speeding electric current is even greater. Battery manufacturers have been 1C charge 70%,2C 60% discharge cycle life test. After this test, can reach 350 cycles of charge and discharge life batteries a lot, but practical by far. This is because the large current increase of 50% depth of discharge, the battery will accelerate the curing. Therefore, the electric motorcycle battery life shorter, because the body was too heavy electric motorcycle, motor power, at the time of the cruise working current up to 8A. Some even up to 10A.

③ charging and discharging frequency

Use in the area of reserve power supply battery, only during power failures will be discharged, if stop 8 times a year, up to 10 years of life, charging only 80 cycles life expectancy, and electric charge-discharge cycle over 300 times a year are common. Even some people may be filled several times a day, charging time is very short, not full use.

④ short charge

Due to electric bike is transport, can charging of time not more, to in 8 hours within completed 36 v or 48 v of 20 Ann Shi charging, this on must improve charging voltage (General for single section 2.7~2.9 v), dang charging voltage over single section battery of analysis oxygen voltage (2.35 v) or analysis hydrogen voltage (2.42 v) Shi, battery on will for excessive analysis oxygen and open valve exhaust, caused loss, makes electrolytic liquid concentration increased, battery of sulfide phenomenon aggravated.

⑤ discharge can not recharge

For commuting, electric bike charging and discharging are completely separated, the discharge conditions and find it difficult to charge and after discharge by the large amount of lead sulfate does not charge to restore if more than half an hour as the lead oxide, sulfide crystal.

The fourth reason: electric bicycle production reasons

Controller set a speed limit of most car plugs, some factory Depot might as well get rid of the speed limiter, which value speed can attract customers, can also reduce costs, such a car traveling at high speed when current is very large, can seriously shorten battery life.

The fifth reason: causes of charging devices

Spread the word in the industry is that battery is not bad, but full of bad. In order to meet short-term high capacity rechargeable batteries for electric bikes, three-stage constant voltage and limited current charging, having to through constant pressure value to 2.47V~2.49V. So, far exceeding the positive electrode plate for battery voltage and negative hydrogen oxygen voltage.

Other reasons

Many batteries in unit testing, you can get better results, but for series batteries, due to capacity, the open circuit voltage, not the same State of charge, the degree of curing, the difference will be expanded in series battery, monomers can affect the whole group with poor battery life decreased significantly.