In the world of electronic devices, there are batteries with monitoring circuitry and then there are those batteries that don’t have such a system. Due to the fact that lithium batteries consist of a printed circuit board that manages the efficiency of the battery, it is considered a smart battery. On the contrary, a basic sealed lead acid battery does not have any board control to enhance its efficiency.
In a smart lithium battery, there are 3 fundamental levels of control. The 3rd level of control is a battery management system known as BMS.
Smart Lithium Battery Balancing Circuit
In a battery with a balancing chip, the chip merely stabilizes the voltages of the specific cells in the battery while it is charging. When all the cell voltages are within a little tolerance of each other, a battery is considered well balanced.
Active balancing happens by utilizing cells with high voltages to charge cells with lower voltages thus lowering the voltage distinction in between the cells up until all cells are carefully matched and the battery is completely charged. Passive balancing, is when each cell has a resistor in parallel that is switched on when the cell voltage is above a certain limit.
In lithium batteries, as soon as the lowest voltage cell reaches the discharge voltage cut off, it will shut down the whole battery. If the cells aren’t stabilized while charging, charging will be disrupted as quickly as the cell with the greatest voltage reaches the cut-off voltage, and not all the cells will be totally charged.
What’s so bad about this? Constantly charging and discharging an imbalanced battery will decrease the battery’s capacity after some time. This likewise suggests that some cells will be totally charged, and others will not, leading to a battery that might never ever reach a 100 % State of Charge.
The theory is that balanced cells all discharge at the very same rate, and for that reason cut-off at the very same voltage. This is not always true, so having a balancing chip guarantees that upon charging, the battery cells’ can be totally matched to safeguard the battery’s capacity and to end up being completely charged.
Lithium Protective Circuit Module
A Protective Circuit Module includes a balanced circuit and extra circuitry that manages the specifications of the battery by protecting against over-discharging and over-charging. It does this by keeping an eye on current, voltages, and temperature levels throughout charging and discharging and comparing them to fixed limitations. The Smart Lithium Battery changes off charging or discharging appropriately till the release technique has actually been fulfilled if any one of the battery’s cells strikes one of those limitations.
There are a couple of methods to turn charging or discharging back on after the defense has actually been tripped. The very first is time-based, where a timer counts for a small percentage of time (for instance, 30 seconds) and after that launches the security. This timer might differ for each defense and is single-level security. The second one is value-based. The voltages all need to drop below 3.6 volts per cell for the over-charging defense to be launched.
The 3rd one is activity-based, where an action should be taken to release the protection. Simply like the value-based defense release, this release might likewise occur right away or be time-based. This might indicate that the load should be gotten rid of from the Smart Lithium Battery for 30 seconds prior to the defense is launched.
Lithium Battery Management System
The most advanced level of control for a lithium battery is the Battery Management System. It preserves the very same functions like the balanced circuit and includes the very same defenses as the PCM. It is different in additional features and advanced protection.
In a PCM, there is a particular defense level. However, in a BMS, there can be numerous levels of defense. Why do you need several levels? This is since the battery can carry out its functions at various levels and might have “surges” in those applications. For instance, the Smart Lithium Battery might experience an in-rush surge current when discharging starts.
The very first level of Over-Current Discharge Protection occurs when the battery discharges in between 20 and 30 amps with a time hold-up of 10 seconds. The 2nd level of security occurs when the battery discharges in between 25 and 35 amps for 3 seconds. The several levels of security enable the battery to discharge at a higher rate to manage surges without harming the battery.
When you have a BMS, there are some extra insights you get. This consists of the State of Charge function, State of Health, cycle count, and extra history of the battery. All these details are extremely beneficial to have over the life of the battery. But, how do you read them? To read this info the Smart Lithium Battery has to have communications protocol. This can be through a wired protocol or a wireless protocol.
If you require the fundamental levels of security, a PCM makes for a terrific alternative as it is the middle of the road circuit for lithium batteries. If you desire to keep track of the battery more carefully and have access to several levels of security, a BMS is the right way to go.
We comprehend that there are numerous elements that enter into choosing the very best smart lithium battery, and our specialists are here to assist you. Please feel totally free to reach out to any of our experts today if you have extra concerns about selecting the ideal battery for your application.