Battery discharge warning .



As we all know, battery discharge warning may sometimes happen, but we seldom discover the reasons and the way to solve it. Here is an article for you to get more knowledge about battery discharge warning.

What does a battery discharge warning mean?

A battery discharge warning means the rate of discharging of your battery is faster than the rate of its charging. This warning will appear with the warning light on, showing electrical problems are occurring. A battery discharge warning can have negative effects and cause some issues.

It activates the battery-safe mode. A high battery discharge rate implies that battery is getting low and needs time to recharge. You should charge it in time. Yet, if the battery still shows a high battery discharge rate, then it is time to replace it.

What is the principle and cause of battery discharge?

What is the principle and cause of battery discharge warning


Battery is at a high risk of discharging while working or even when not in use. let's discuss the principle and causes of this discharging.

  • Harsh Environment:  External temperature directly affects the discharge rate of the battery. The battery discharge rate goes on increasing with higher temperature. Always store a battery at a room temperature with 20-25 Degrees Celsius.
  • Malfunctioning Charging Circuit: The battery charging system consists of three components: a sensor, alternator, and starter. If one of them is not functioning properly, it will discharge the battery faster and cause a battery discharge warning.
  • Floppy Terminal: A loose battery terminal ruins the battery and wastes electricity even when the battery is in an inactive condition.
  • Aging Battery: An ageing battery can cause a battery discharge warning. It is because of almost nearing the end cell cycle of the old battery.
There are many other causes like broken chargers, the poor ground connection, and corroded battery terminals that cause a battery discharge warning.

Can a battery be charged and discharged at the same time?

No! Normal battery is not allowed to be charged and discharged simultaneously. It can do either charging or discharging. For example, if you are charging battery with alternator, When the alternator has a voltage lower than the battery, the battery is going to supply the current to the load. It is being discharged instead of charged. If the alternator has a higher voltage, then the battery is being charged and does not supply current to the load. The reactions and results of the two processes of charging and discharging are different, so they cannot be carried out at the same time.

How to solve battery discharge warning? Does common power equipment also present a warning? 

Yes! Common power equipment can also present warnings. If your battery gets a discharge warning, you have few options to resolve it if using lead acid battery.

  • First,examine the electrolyte levels. If there is no electrolytein the battery, there will be no current distribution to the terminals.
  • Jumpstart is the simplest way to revive a drained battery. In this technique, a jumper cable uses to connect a discharged battery with a charged battery.
  • If there is a problem with a module in the battery, you can replace the module. But in general, it is recommended to send it back to the battery factory for repair or replace it with a new one.

What factor affects the battery discharge?

What factors affect battery discharge in battery discharge warning


Normal battery discharge depends on the battery's discharge c rate. If the discharge rate of the battery during use is higher than the original parameter value, it means that the battery has a problem or is in an abnormal working state.The battery discharge rate increases with ageing, recycling, and temperature. Let us discuss the factors which affect the discharge rate of the battery and cause a battery discharge warning.

① Elevated temperature

The discharge rate of the battery increases with an increase in temperature. The discharge rate of a battery becomes doubles with the rising in temperature.

② State of charge (SOC)

Battery state of charge also affect the discharge rate of the battery. The fully charged batteries discharged more than those with no full charge.

③ Depth of discharge (DOD)

DOD also affects the discharge rate of the battery. The theoretical cycle life of batteries with a DOD of less than 80% has been exhausted and can be scrapped or recycled, and the natural discharge rate will be relatively high.

What does a high battery discharge rate imply for the battery?

The higher discharge rate for the battery implies that it loses more capacity than normal. It means a battery degrades and has less energy with the same electricity input. Thus, a high discharge rate of the battery implies the damage to a battery. Also, it means there may be something wrong with the battery which needs fixing. If battery discharge warning can not be solved in time, the battery may become dead battery.

FAQs about battery discharge warning

When not in use, why do batteries discharge? All the batteries produce electric current due to a chemical reaction. This reaction will occur when a battery is connected to the load. However, this chemical reaction can also take place at a smaller scale of device, even when a battery is not in use. That is why all batteries have a self-discharge rate, even if they are not at work. While lithium battery has low self-discharge rate. 

When a battery is drained, what voltage does it have? Your battery will be drained when it loses energy or voltage and give no response to the output devices. For 3.7V lithium battery, the ideal full charge voltage of the lithium battery is 3.0v, the battery may be damaged if the voltage exceeds 3.0v.

Will the battery discharge rate change? What will it change with?

Will the battery discharge rate change in battery discharge warning


Under normal working conditions, it will not change depending on the c rate. A C-rate is a unit to express the discharge current of a battery against its maximum capacity. The discharge rate of 1c means that the battery is discharged in one hour, and the discharge rate of 0.5c means that the battery is discharged in two hours. It means the higher the C-rate, the faster the discharge time and vice versa.

Is the battery self-discharge normal?

Yes! the battery self discharge is a perfectly normal phenomenon. Self-discharge means the battery loses its energy or voltage even when not in use.

What is the self-discharge rate of different kinds of batteries?

Different kinds of batteries experience different self-discharge rates depending on their nature and chemistry. Lead-acid and Ni-Cd batteries have very high self-discharge rates and quickly lose their charge. They have a 25% self-discharge rate per month. The self-discharge rate of the lithium-ion battery is 3.5% per month. The self-discharge rate of lead-acid batteries is 0.5~1%/day. Lithium-ion batteries have the highest self-discharge rates.

Can we fully discharge a battery?

No! a battery is not recommended to be fully discharged in working condition . Because it is likely to cause overdischarge and too low voltage and affect the performance of battery. A lithium-ion battery should not discharge below 2.5V/cell as this may cause capacity loss and safety issues. The general recommendation is to charge to 80% and discharge to 20%. Overcharging and overdischarging will damage the battery.

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