E-bike battery soldering is a process that is used to connect e-bike batteries. There are two main soldering methods:
- The automatic spot soldering machine method (for batteries and BMS)
- The handheld soldering method using a soldering iron (for BMS)
Some of the tools used in handheld lithium battery soldering for PCB (BMS) include:
- Finger cover, electrostatic ring, soldering iron, welding fixture
Soldering can be used for packing (for ex. connectors); soldering the wires (copper wire) together and wrapping the solder splice with heat shrink.
How to solder lithium batteries?
The lithium battery soldering process can be used to join a wide variety of metal components of an e-bike battery including the battery management system.
Large factories have devised ways of ensuring faster soldering of the entire pack of e-bike lithium batteries to match up with their mass production. In the mass production of e-bike batteries, the Automatic Spot Soldering machine comes in handy.
The lithium-ion cells for the electric bicycle battery are placed on a conveyor belt that moves it along to the next stage of the process.
The whole e-bike battery spot welding process takes less than 2 minutes on all the cells. A nickel plate is used for this soldering process. Nickel strip is a little bit more expensive than nickel-plated steel but it has much lower resistance. A single spot weld is very quick and takes less than a second, making it impossible to resolder. After, a spot soldering inspection is done.
Advantages of automatic spot soldering in lithium batteries for e-bikes
-The automatic spot soldering process is faster than conventional methods. As opposed to a hand-held soldering iron, the automatic spot soldering machine is faster and more accurate.
-It produces e-bike batteries of consistent quality in a controlled manner.
-The e-bike battery is less likely to be damaged during the soldering.
-No need to spend a lot of time in order to dry them after soldering.
-The e-bike battery soldering process is clean and does not produce any harmful fumes and there are minimal chances of explosion
-The e-bike battery cells are placed in the battery case in the correct position with no room for errors.
Disadvantages of automatic spot soldering in lithium batteries for e-bikes
-The e-bike battery pack case and other cells need to be placed in the correct position.
-It requires specially trained staff to ensure the quality of the whole pack.
-A wrong handling can lead to an explosion and fire outbreak and be risky. Proper care should be taken to avoid heating which may make the bad cell catch fire.
Features of e-bike battery cells soldered automatically
The making of e-bike batteries through the automatic resistance soldering machine leads to high-quality results in the final product. This includes:
- Longer life for both the battery pack and the battery management system
- E-bike batteries that are not damaged easily
- E-bike batteries of consistent quality
- Strong and durable e-bike batteries with less heat damage
Types of battery connections
Parallel cells soldering involves connecting two lithium battery cells or more e-bike battery cells in parallel groups. This is done by soldering the positive end of one cell to the positive end of the other cell and then soldering the negative end of one cell to the same side of the negative end of the other cell.
The parallel battery cells increase the capacity of the e-bike battery and allow it to discharge current at a much higher rate.
The soldering of lithium cells on series connections involves connecting the e-bike cell groups in a series connection. This is done by soldering the positive terminal of an individual cell to the negative terminal of the other individual cell and then soldering the negative end of the one cell to the positive wire/terminal of the other cell.
This type of connection increases the voltage of the e-bike battery.
Is it safe to solder lithium-ion e-bike batteries?
Yes, it is safe if safety measures are followed, correct equipment such as an automatic soldering machine is used and there are trained staff. If you need to use a handheld soldering method using a soldering iron for BMS or pack, it requires specially trained staff and strict safety measures.