Customized battery systems - Lithium Storage

Welcome to LITHIUM STORAGE, your trusted partner in the lithium battery industry. We specialize in providing customized lithium-ion battery systems tailored to meet your specific needs. With cutting-edge technology, sustainable practices, and a commitment to innovation, we deliver power solutions that drive progress in a wide range of industries.

Lithium Storage are exported all over the world and different industries with quality first. Our belief is to provide our customers with more and better high value-added products. Let's create a better future together.

Select Lithium Cells for Your Needs

Lithium batteries encompass a diverse array of electrochemical technologies and physical designs, making it challenging to identify the ideal option for your specific needs. At LITHIUM STORAGE, we simplify this process by helping you choose the perfect cell from our extensive catalog.

Our selection process involves a detailed analysis of key usage factors, including charge and discharge power, operating time, temperature range, size, weight, and lifespan. By evaluating these parameters, we identify the most suitable cell to ensure optimal battery performance and extended longevity.

BMS (Battery management system)

The Battery Management System (BMS) is an advanced electronic module designed to control, monitor, and ensure the safe operation of lithium batteries. It enables intelligent and adaptable management of the battery’s charging and discharging processes.

At LITHIUM STORAGE, our BMSs are the result of extensive experience and continuous innovation, incorporating insights from numerous successful projects. Developed entirely in-house, our BMSs are highly adaptable and modular to meet the unique needs of each customer. They measure, calculate, and control hundreds of advanced parameters in real-time, ensuring optimal battery performance.

The BMS ensures continuous balance among the cells in the battery pack. Unlike most systems that limit balancing to the end of charging, our BMS monitors each cell in real-time and applies unique charging and discharging rules throughout both charging and discharging phases. This approach maintains uniformity across the pack at all times.

Guaranteeing Superior Quality with 100% Testing

Ensuring the safety and performance of a battery requires a comprehensive series of tests, including cell evaluations, welding integrity checks, battery cycling tests, and more.

At LITHIUM STORAGE, every cell, weld, and assembled battery undergoes rigorous testing to guarantee top-tier quality. Our systematic unit testing, combined with the capabilities of our semi-automatic production line, allows us to produce custom lithium batteries at scale with unmatched reliability and complete traceability.

Custom Battery Key Features

✔️ Tailored Specifications: Customizable voltage, capacity, and configurations to meet unique power and energy demands.

✔️ High Energy Density: Delivers more power in a compact size, ideal for space-constrained applications.

✔️ Advanced Battery Management System (BMS):

    Real-time monitoring of voltage, current, and temperature.

    Protection against overcharge, over-discharge, short circuits, and thermal runaways.

✔️ Modular Design: Scalable systems that allow for easy expansion as energy requirements grow.

✔️ Longevity: Designed for extended cycle life, ensuring durability and cost-effectiveness.

✔️ Fast Charging: Supports rapid charging technology for minimal downtime.

✔️ Eco-Friendly: Focused on sustainability with recyclable materials and lower environmental impact.

Applications of Custom Battery Systems

Our custom battery systems are designed to meet diverse energy needs across industries, offering reliable and efficient power solutions. They are widely used in renewable energy storage, ensuring stable power supply for solar and wind systems. In electric vehicles, our batteries deliver long-lasting performance and fast charging. For industrial equipment like forklifts and robots, they provide durable and energy-efficient operation. Our batteries also power medical devices, telecommunications infrastructure, and portable power stations, ensuring uninterrupted performance in critical applications. Whether for grid stabilization, smart home devices, or specialized machinery, our custom battery systems are tailored to optimize performance and meet your specific requirements.

Contact us today to get a quote and discover the perfect energy solution for your business.

Why Choose LITHIUM STORAGE ?

✔️ We provide fully customizable battery systems, including solutions that comply with VDA, VDE, MED, and national standards.

✔️ Our products leverage the latest in LFP/NCM lithium-ion chemistry to ensure high performance and reliability.

✔️ Committed to reducing environmental impact, we develop batteries that support the transition to a low-carbon economy.

The company is the world’s best Battery Energy Storage Solution supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.

✔️ With a factory in Wenzhou, a technical team in Nanjing, and an international branch in Dundee, UK, we deliver solutions globally.

✔️ Our production meets the highest international standards, including ISO, IATF, ISO, and ISO, and our products hold certifications like MSDS, UN38.3, UL, IEC, JET, and BIS.

How It Works

It’s easy to request a custom battery systems. Simply follow the steps below and we will send you a quote for the requested custom battery pack.

✔️ Fill out the Custom Battery Request Form.

✔️ Engineers will determine the specifications for the requested battery pack.

✔️ LITHIUM STORAGE will send you a quote with the battery system, the specifications, and associated information.

Battery management systems do not have a fixed or unique set of criteria that must be adopted. The technology design scope and implemented features generally correlate with:

• The costs, complexity, and size of the battery pack
• Application of the battery and any safety, lifespan, and warranty concerns
• Certification requirements from various government regulations where costs and penalties are paramount if inadequate functional safety measures are in place

There are many BMS design features, with battery pack protection management and capacity management being two essential features. We’ll discuss how these two features work here. Battery pack protection management has two key arenas: electrical protection, which implies not allowing the battery to be damaged via usage outside its SOA, and thermal protection, which involves passive and/or active temperature control to maintain or bring the pack into its SOA.

Electrical Management Protection: Current

Monitoring battery pack current and cell or module voltages is the road to electrical protection. The electrical SOA of any battery cell is bound by current and voltage. Figure 1 illustrates a typical lithium-ion cell SOA, and a well-designed BMS will protect the pack by preventing operation outside the manufacturer’s cell ratings. In many cases, further derating may be applied to reside within the SOA safe zone in the interest of promoting further battery lifespan.

Lithium-ion cells have different current limits for charging than for discharging, and both modes can handle higher peak currents, albeit for short time periods. Battery cell manufacturers usually specify maximum continuous charging and discharging current limits, along with peak charging and discharging current limits. A BMS providing current protection will certainly apply a maximum continuous current. However, this may be preceded to account for a sudden change of load conditions; for example, an electric vehicle’s abrupt acceleration. A BMS may incorporate peak current monitoring by integrating the current and after delta time, deciding to either reduce the available current or to interrupt the pack current altogether. This allows the BMS to possess nearly instantaneous sensitivity to extreme current peaks, such as a short-circuit condition that has not caught the attention of any resident fuses, but also be forgiving to high peak demands, as long as they are not excessive for too long.

Electrical Management Protection: Voltage

Figure 2 shows that a lithium-ion cell must operate within a certain voltage range. These SOA boundaries will ultimately be determined by the intrinsic chemistry of the selected lithium-ion cell and the temperature of the cells at any given time. Moreover, since any battery pack experiences a significant amount of current cycling, discharging due to load demands and charging from a variety of energy sources, these SOA voltage limits are usually further constrained to optimize battery lifespan. The BMS must know what these limits are and will command decisions based upon the proximity to these thresholds. For example, when approaching the high voltage limit, a BMS may request a gradual reduction of charging current, or may request the charging current be terminated altogether if the limit is reached. However, this limit is usually accompanied by additional intrinsic voltage hysteresis considerations to prevent control chatter about the shutdown threshold. On the other hand, when approaching the low voltage limit, a BMS will request that key active offending loads reduce their current demands. In the case of an electric vehicle, this may be carried out by reducing the allowed torque available to the traction motor. Of course, the BMS must make safety considerations for the driver the highest priority while protecting the battery pack to prevent permanent damage.

Thermal Management Protection: Temperature

At face value, it may appear that lithium-ion cells have a wide temperature operating range, but overall battery capacity diminishes at low temperatures because chemical reaction rates slow down remarkably. With respect to capability at low temperatures, they do perform much better than lead-acid or NiMh batteries; however, temperature management is prudently essential since charging below 0 °C (32 °F) is physically problematic. The phenomenon of plating of metallic lithium can occur on the anode during sub-freezing charging. This is permanent damage and not only results in reduced capacity, but cells are more vulnerable to failure if subjected to vibration or other stressful conditions. A BMS can control the temperature of the battery pack through heating and cooling.

Realized thermal management is entirely dependent upon the size and cost of the battery pack and performance objectives, design criteria of the BMS, and product unit, which may include consideration of targeted geographic region (e.g. Alaska versus Hawaii). Regardless of the heater type, it is generally more effective to draw energy from an external AC power source, or an alternative resident battery purposed to operate the heater when needed. However, if the electric heater has a modest current draw, energy from the primary battery pack can be siphoned to heat itself. If a thermal hydraulic system is implemented, then an electric heater is used to heat the coolant which is pumped and distributed throughout the pack assembly.

BMS design engineers undoubtedly have tricks of their design trade to trickle heat energy into the pack. For example, various power electronics inside the BMS dedicated to capacity management can be turned on. While not as efficient as direct heating, it can be leveraged regardless. Cooling is particularly vital to minimize the performance loss of a lithium-ion battery pack. For example, perhaps a given battery operates optimally at 20°C; if the pack temperature increases to 30°C, its performance efficiency could be reduced by as much as 20%. If the pack is continuously charged and recharged at 45°C (113°F), the performance loss can rise to a hefty 50%. Battery life can also suffer from premature aging and degradation if continually exposed to excessive heat generation, particularly during fast charging and discharging cycles. Cooling is usually achieved by two methods, passive or active, and both techniques may be employed. Passive cooling relies on movement of air flow to cool the battery. In the case of an electric vehicle, this implies that it is simply moving down the road. However, it may be more sophisticated than it appears, as air speed sensors could be integrated to strategically auto-adjust deflective air dams to maximize air flow. Implementation of an active temperature-controlled fan can help at low speeds or when the vehicle has stopped, but all this can do is merely equalize the pack with the surrounding ambient temperature. In the event of a scorching hot day, this could increase the initial pack temperature. Thermal hydraulic active cooling can be designed as a complementary system, and typically utilizes ethylene-glycol coolant with a specified mixture ratio, circulated via an electric motor-driven pump through pipes/hoses, distribution manifolds, a cross-flow heat exchanger (radiator), and cooling plate resident against the battery pack assembly. A BMS monitors the temperatures across the pack, and open and closes various valves to maintain the temperature of the overall battery within a narrow temperature range to ensure optimal battery performance.

Capacity Management

Maximizing a battery pack capacity is arguably one of the most vital battery performance features that a BMS provides. If this maintenance is not performed, a battery pack may eventually render itself useless. The root of the issue is that a battery pack “stack” (series array of cells) is not perfectly equal and intrinsically has slightly different leakage or self-discharge rates. Leakage is not a manufacturer defect but a battery chemistry characteristic, though it may be statistically impacted from minute manufacturing process variations. Initially a battery pack may have well-matched cells, but over time, the cell-to-cell similarity further degrades, not just due to self-discharge, but also impacted from charge/discharge cycling, elevated temperature, and general calendar aging. With that understood, recall earlier the discussion that lithium-ion cells perform superbly, but can be rather unforgiving if operated outside a tight SOA. We learned previously about required electrical protection because lithium-ion cells do not deal well with over-charging. Once fully charged, they cannot accept any more current, and any additional energy pushed into it gets transmuted in heat, with voltage potentially rising quickly, possibly to dangerous levels. It is not a healthy situation for the cell and can cause permanent damage and unsafe operating conditions if it continues.

The battery pack series cell array is what determines the overall pack voltage, and mismatch between adjacent cells creates a dilemma when attempting to charge up any stack. Figure 3 shows why this is so. If one has a perfectly balanced set of cells, all is fine as each will charge up in equal fashion, and the charging current can be cut off when the upper 4.0 voltage cut-off threshold is reached. However, in the unbalanced scenario, the top cell will reach its charge limit early, and the charging current needs to be terminated for the leg before other underlying cells have been charged to full capacity. 

The BMS is what steps in and saves the day, or the battery pack in this case. To show how this works, a key definition needs to be explained. The state-of-charge (SOC) of a cell or module at a given time is proportional to the charge available relative to the total charge when fully charged. Thus, a battery that resides at 50% SOC implies it is 50% charged, which is akin to a fuel gauge figure of merit. BMS capacity management is all about balancing the variation of the SOC across each stack in the pack assembly. Since the SOC is not a directly measurable quantity, it can be estimated by various techniques, and the balancing scheme itself generally falls into two main categories, passive and active. There are many variations of themes, and each type has pros and cons. It’s up to the BMS design engineer to decide which is optimal for the given battery pack and its application. Passive balancing is the easiest to implement, as well as to explain the general balancing concept. The passive method allows every cell in the stack to have the same charged capacity as the weakest cell. Using a relatively low current, it shuttles a small amount of energy from high SOC cells during the charging cycle so that all cells charge to their maximum SOC. Figure 4 illustrates how this is accomplished by the BMS. It monitors each cell and leverages a transistor switch and an appropriately sized discharge resistor in parallel with each cell. When the BMS senses a given cell is approaching its charge limit, it will steer excess current around it to the next cell below in a top-down fashion.