The batteries of SOUOP portable power station all use BMS because the battery can easily cause fire, SOUOP does its best to make the battery well to avoid any accident. So what is BMS, let Xiaobian come to popular science.
What is a battery management system?
Definition
A battery management system (BMS) is a technology dedicated to overseeing battery packs, which are assemblies of battery packs, electrically organized in a row-by-column matrix configuration to provide a target range of voltages and currents throughout expected load conditions.
Oversight provided by a BMS typically includes:
- monitor battery
- Provides battery protection
- Estimating the operating state of the battery
- Continuously optimize battery performance
- Report operational status to external devices
Here, the word “battery” means the entire battery pack; however, monitoring and control functions apply exclusively to individual cells or packs of batteries called modules within the overall pack assembly. Lithium-ion rechargeable batteries have the highest energy density and are the standard choice in battery packs for many consumer products, from laptops to electric vehicles. While they are excellent performers, they can be quite relentless if operated outside the often compact Safe Operating Area (SOA), with consequences ranging from compromising battery performance to downright dangerous. A BMS is an undeniably challenging job description whose overall complexity and scope of oversight may span many disciplines such as electrical, digital, controls, thermal, and hydraulics.
How does the battery management system work?
The battery management system monitors the individual cells in the battery pack. It then calculates how much current can safely enter (charge) and flow out (discharge) without damaging the battery.
Current limiting prevents the source (usually a battery charger) and load (such as an inverter) from overusing or overcharging the battery. This protects the battery pack from too high or too low battery voltage, helping to extend the battery’s lifespan.
The BMS also monitors the remaining charge in the battery. It continuously tracks the energy going in and out of the battery pack and monitors the battery voltage. It uses this data to know when the battery is depleted and turn it off. That’s why lithium-ion batteries don’t show signs of dying like lead acid, but just shut down.
Why BMS Matters
Battery management systems are critical to protecting the health and longevity of batteries but are even more important from a safety perspective. The liquid electrolyte in lithium-ion batteries is highly flammable.
Therefore, these batteries need to perform optimally within safe limits at all times to prevent fires.
Functional safety is paramount in BMS. During charging and discharging operations, it is critical to prevent the voltage, current, and temperature of any monitored cell or module from exceeding the defined SOA limits. If the limit is exceeded for some time, not only can a potentially expensive battery pack be damaged, but a dangerous thermal runaway condition can occur. In addition, lower voltage threshold limits are strictly monitored to protect Li-Ion batteries and functional safety. If lithium-ion batteries are kept in this low-voltage state, copper dendrites will eventually grow on the anode, which can lead to higher self-discharge rates and potential safety concerns. The high energy density of lithium-ion powered systems comes at the expense of leaving little room for battery management error. Due to BMS and Li-ion improvements, this is one of the most successful and safest battery chemistries available today.
The performance of the battery pack is the second most important characteristic of a BMS, which involves electrical and thermal management. To electrically optimize overall cell capacity, all cells in a battery pack need to be balanced, which means that the SOCs of adjacent cells in the entire assembly is approximately equal. This is important because not only does optimal battery capacity result, but it helps prevent overall degradation and reduce potential hot spots from overcharging weak batteries. Li-ion batteries should avoid discharging below the low voltage limit as this can lead to memory effects and significant capacity loss. Electrochemical processes are highly sensitive to temperature, and batteries are no exception.
When the ambient temperature drops, the capacity, and available battery energy drop significantly. Therefore, the BMS can use an external in-line heater, which is located on the liquid cooling system of the battery pack of an electric vehicle or turn on the resident heater plate under the battery pack module installed in a helicopter or other equipment. airplane. Furthermore, since charging cold Li-ion batteries is detrimental to battery life performance, it is important to fully raise the battery temperature first. Most Li-Ion batteries cannot be fast charged below 5°C and should not be charged at all below 0°C. For optimum performance during typical operational use, BMS thermal management typically ensures that the battery operates within the narrow Goldilocks operating area (eg 30 – 35°C). This guarantees performance.
SOUOP product built-in battery management system
All SOUOP product batteries have built-in BMS. This prevents all the most common causes of battery failure and danger.
These include protecting the battery from short circuits, high currents, overheating, overcooling, and high or low voltages. The built-in BMS of the SOUOP portable power station also prevents failures.