Cordless power tools are convenient, but they are only as reliable as their rechargeable batteries. The moment the battery runs out, the tool is useless.
Despite the fact that a battery is “dead”, it is only partially dead, making it possible to re-use it. In this article, you’ll learn about two ways to jumpstart a dead lithium battery. First, you need to check whether the battery is dead. The best way to jumpstart a battery is not to charge it in the wrong way. Read: How to Charge a Dead Lithium-Ion Battery – Charging And Reviving for more information.

Can you jumpstart a lithium battery at home?

In order to jumpstart a dead battery, you will need one fully charged battery, which you can place next to the dead battery.
Connect two short insulated wires with polarity matching between the two batteries, positive to positive and negative to negative.
After waiting for about five minutes, you need to disconnect the wires and place the dead battery in the battery charger of the tool. This method will transfer power from the live battery to the dead battery. When the battery gains charge, the jumpstart is working. Charge it for an hour or until full charge.
If the battery does not get charged, you can try jumpstarting it again, but if the battery does not get charged, it probably needs to be replaced.

Other methods to jumpstart the battery:

Increase the Voltage
This method is also used in jumpstarting lithium batteries. To ensure consistency in battery health, you should be able to turn on any lithium-powered devices at least once every two days. If left unused for too long, lithium batteries will die.
It is important to note that it is risky. If you overcharge for too long, then it is probable that the battery will explode. You must wear eye goggles and perform the process in a large area. The first step is to locate the positive and negative inputs on your battery. It should be clearly labeled. In the absence of labels, you can search Google for battery level information.
The next step is to cut two pieces of wire. Each wire should measure near about 2.75 inches. One battery wire serves as the positive wire, the other serves as the negative wire. On the positive wire, remove the protective coating from both ends, which is about 0.4 inches in length. On the negative wire, remove about 0.4 inches on one end and just 0.8 inches on the other.
Insert the positive wire into the battery’s positive pinout and the 0.4-inch end of the negative cable into the negative pinout when ready.
Lastly, you have to attach the 0.8 inches of the negative cable to the negative outer conductor using the clip at the end of the negative cable.
When disconnecting the setup, take care to avoid explosions. After the entire process is complete, reinsert the battery to see if the jumpstart was successful.

Replace Battery Cells

A knife and flat head screwdriver are required to remove the battery from the device and replace it with cells from a working but unused battery.
There will be a series of individual cells inside the battery. These cells will be connected to a circuit board with wires. You should use a multimeter to ensure that there are no residual charges.
Using the soldering tool, you must separate the cells from their wires, and then you have to remove them from the case. Your new cells should then be soldered together and wires should be reconnected. Last but not least, reassemble the battery’s casing and let it rest for 48 hours to ensure the soldering has set.

There are a few cautions that you need to keep in mind:

Replacement cells should have the same chemistry as compared to current cells
New cells should have the same rated voltage as the old ones.
New cells must have the same or higher capacity as old cells.
The size of the new cells must be the same as the old cells.
Soldering tool is required.

What tools do you need when you jumpstart a lithium battery?

Jumpstarting a battery is straightforward. Some basic tools are required, and these are:
There is a requirement for various sizes, but it is best to have a size from 3mm to 5mm. Avoid using thick blades that take up a lot of space and become difficult to store.
To separate cases, use a spudger made of metal or strong plastic.
The side cutters and flash cutters are useful for cutting the battery or thick tabs and wires. The flash cutters are better for splitting cells.
It would be better to use a utility knife than a spudger if you have one.
Voltage can be measured with a multimeter.
To protect against sharp edges of the equipment, gloves are used for this task.

Can you use a regular battery charger on a lithium battery?

This battery can be used if you use a suitable battery charger. If you do not, the battery will be damaged. Proper charging allows the battery to perform better and last longer.
Once fully charged, they need to be stopped, as they will get swollen or catch fire. The normal lithium-ion batteries require 4.2 Volts per cell to be charged.

Conclusion

You can avoid landing yourself in a situation of jumpstarting the battery if you take care of it regularly. It is recommended that you monitor the battery report of your devices.