Intelligent Energy Storage
Balancell has been manufacturing smart lithium batteries since 2009. Combining leading edge technology with the latest mechanical and electronic design principles, we have developed a comprehensive range of batteries with a proprietary battery management system and our own globally connected IOT data platform.
Our batteries are specifically engineered for demanding applications that require lightweight, robust and high capacity batteries that manage themselves, protect themselves and report their use and condition remotely. The following features are useful in all applications, but particularly relevant to industrial motive machines.
Laboratory Accuracy BMS
Our Battery Management System (BMS) was first developed in 2001 and was designed to be chemical agnostic. This ability to be used with a variety of battery chemistries has over the years produced many insights and experiences that have given rise to a host of design improvements and unique features. Early in our BMS development we saw the value of batteries being connected and built our own connectivity modules and a IOT gateway. This allowed us to collect extremely accurate battery information in the field and measure parameters such as coulombs and energy and use that data for battery analysis, machine system analysis, and early failure predictions.
This collection and analysis of battery data has allowed us to build an exceptionally accurate Battery Management System with a 1:500 000 dynamic range on both voltage and current measurement. A dynamic range this big means it can resolve 1mA changes and measure up to 500A. Even more exceptional, is that with this dynamic range it also has has an extremely low offset of less than 10mA. This enables our BMS to measure coulombs in, coulombs out and coulombic efficiency with enough accuracy to be scientifically meaningful, and to do lifetime predictions. Another example of how useful this is, our State of Charge (SOC display value) is considerably better than 0.1% accurate in a normal daily charge/discharge cycle, and only typically drifts by considerably less than 0.1% per day when left idle.
In addition to just battery and machine analysis, the data can provide very useful business metrics and value adds. In terms of machine drive or battery diagnostics, our BMS technology can do a simultaneous multichannel oscilloscope capture on every cell voltage, battery voltage and battery current, and send all these readings back wirelessly to our gateway. Our accuracy also extends to every individual cell, as every cell voltage is measured as a virtual four-terminal measurement, directly across cell terminals and excluding any interlink voltage drops. There are no common measurement or sense wires with adjacent cells as these give noise and inaccuracies, and all cell voltages are measured simultaneously, together with battery voltage and current. These simultaneous measurements are necessary to calculate battery impedances, and for the 3D state space models. The number of balancing coulombs per individual cell is also measured and reported. The cell voltages are all measured simultaneously to within a microsecond, as these are imperative for any cell impedance or SOH calculations.
Modular Battery Management System (BMS) with built in logic that provides multiple layers of analogue and digital protection
Battery and Machine Analysis
Distributed Battery laboratory
Collecting accurate battery data also allows in-depth analysis of both battery and of the machine operation it is used in. This operational data can be used to generate businesses value add metrics and reports. For example, hours operated, hours charged, usage patterns, but it can also generate more unique data, such as how efficient is a particular machine is at doing a job (measured classically with VDI cycle in kWh/h).
Another example of our unique analysis ability is our data could be used to calculate actual live work rates, giving an indication of how busy the machine is, or report on busy periods. Operational improvements are also possible, for example, in rental access or cleaning machines, we generate alerts that prevent downtime such as battery not put on charge at end of shift.
Using our accurate data gathered from every battery, we are developing innovative 3D state space models to represent each battery that give a very powerful visual and analytical means to diagnose problems, view performance degradation, generate early warnings, and do lifetime predictions.
Our aim is to turn this concept into a very intuitive and powerful tool for evaluating vast amounts of battery data in the field, either of deployed batteries or of any new chemistry, without needing extensive laboratories or software. We aim to become the largest “distributed battery laboratory” in the world.
Global Wireless Connectivity
We can offer lifetime (15 year prepaid) global connectivity using our GSM connectivity options including 2G, 3G and NB-IoT. GSM is ubiquitous globally and has the bandwidth needed and has been our focus as most suited to motive applications. We do also offer Wifi connectivity, and we are developing software to make a battery visible on a local LAN network.
Power Electronics Integration
Our solid-state contactor (referred to as the “Smart E switch”) is unique at higher battery voltages and currents, operating up to 80V, 1000A.
Solid-state does have limitations in terms of maximum voltages, but also offers many unique features, such as high efficiency, low resistance, unlimited on/off life, compact size, low power drive requirements, and ability to offer electronic current limits.
This means it can also act as built-in pre-charge circuitry. It is easily configurable for multiple battery types. The easy drive, low power means it is relatively easy to add a layer of analogue electronic safety battery cut outs, as a failover from digital cut outs.
Over 1 billion minutes of customer data processed in the cloud
The unrealized Safety benefits of a battery being connected online permanently are substantial.
Our BMS measures battery parameters with enough accuracy, that the data can show when a single connection is starting to come loose or cell performance is degrading. With correct algorithms, these types of failures can be predicted well ahead of time. Service departments can hence plan ahead, and customers will not have any downtime.
All battery information can be analysed in real-time on the server side, with alerts and warnings generated if something is going wrong. Even simple warnings, such as battery should be put on charge, can help prevent a dangerous over-discharge condition, but is also very useful in saving the battery itself and preserving the value and life of the battery. The same can be said for overcharge or over-temperature etc. As algorithms improve the warning predictions will become more accurate and will happen further ahead of time, preventing any damage to the battery, or downtime to operations.
Connectivity also enables a Remote shutdown to be initiated if necessary. This can be done by Server analytics, with or without human intervention. Our system and batteries have the ability to do this, but usually, the battery will protect itself first.
Cells Certified Safety
We only use Lithium Ferro Phosphate Chemistry (LFP) cells that meet GB31484, GB31485, GB31486, UL1973, MSDS UN38.3, and manufactured to ISO9001, ISO14001, TS16949.
Battery Safety Standards
Batteries have been designed to exceed IEC 62485-6, IEC 63056, IEC 61619, and automotive temperature and vibration standard IEC 62660-2. Our batteries have been internally tested far in excess of these limits, as well as proven field performance. Batteries have been tested for EMC and certified to CE standards, by an approved test house.
Short Circuit protection.
Our batteries are unique in that they have both Electronic short circuit protection and Fuse protection. The Electronic short circuit protection is performed with our solid-state contactor, referred to as the Smart E-Switch.
Dual redundant Digital and Analog protection
All batteries have digital protection, but if it has failed or not responding there is also failover analogue protection provided by the Smart E-switch. The analogue limits are just a little over the digital limits.
Automatic pre charge
The fast-acting electronic current limit prevents excessive currents and damage to both inverter and controller input capacitors. In addition, the input Contactor life will be extended as this automatic pre charge reduces most of the arcing due to contactor bounce during key-on events.
Over voltage protection
If the battery is full or overvoltage present, the Electronic Smart E-switch will disable only the top half of the contactor, meaning the battery cannot be charged further – But it is still instantly available for discharge through the internal diodes of the Smart E-switch. This is a very useful feature in terms of home storage inverters, UPS systems, or direct charging from solar panels.
Deep discharge protection
When left for six months out of season, even if batteries are left with less than 20% SOC, our very low power analogue circuitry will disconnect the BMS and prevent deep discharge.
Battery Assembly Technology & Lean Manufacturing
Our modular BMS and battery technology allowing us to assemble prismatic cells directly into a battery, or referred to as “cell direct to pack”.
Our production line has been designed and implemented with the best of batch and lean manufacturing principles and is itself a modular production line.
This means we can simply replicate the line and scale production fast. Our modular BMS and battery assembly technology also gives us the ability to produce new designs very quickly and take them directly into production.
The Balancell LFP Battery range is designed to be totally maintenance free
Robust, Light, & Optimum Form Factors
We have a cell compression method using a unique parallel expansion plate that acts to tension the exoskeleton battery box as well. The combined compressed cells and tensioned exoskeleton battery box gives structural rigidity with no added weight.
The cells make up 80 – 87% of the weight on all our battery models. Compressed cells, together with tension bars and battery casing, means the cells are held in place from all six sides, making the battery itself tolerant to rotation and inversion. Extra cell insulation made from approved PET is also added to every individual cell.
This extra insulation, together with cell compression, tension bars, flexible interlinks and tensioned exoskeleton battery box make the battery physically robust and tolerant to vibration, shocks, dropping and temperature cycling, while still being easily accessible in the field for service and repair.
In addition to the exoskeleton casing, our direct cell to pack methodology and solid-state contactor allows us to make the smallest battery form factors possible using standard automotive prismatic cells.
On a typical battery, the specific energy density is 145Wh/kg and volumetric density is 220Wh/l.
Guarantee & Accountability
The guarantee or warranty offered by many manufacturers are often not as comforting as they appear at face value, such as a long calendar lifetime of 10 years. The warranty is often prorated and discounted over the lifetime to the original value, and then only offered as a discount on a new purchase.
In addition, there are usually a few other rejecting conditions. The better question to ask is, how is the performance of the battery over its lifetime proven, or disproved? For example, how does the customer demonstrate that the battery was always used within specification, as this will be the first point of refusal on a claim. Secondly, “cycles” is not a useful metric, as lithium can do many more “small” cycles than typically specified in datasheets for 100% DOD.
Industrial motive applications are very high cycling applications as with opportunity charging, there can be many smaller cycles in a day. Hence, a more useful metric in this context is how many machine operating hours did the battery work for. This is proportional to how much work the battery does, or the total amount of energy the battery has delivered. Balancell BMS has the ability to measure energy input and energy output exactly and provide a guarantee based on this.
The entire battery history, of every parameter, is recorded for every minute up to 30 years internally (and sent to our gateway if online).
The Total Energy Output in kWh, or total lifetime operating hours are all recorded. The data is all transparent and accessible to either honour the guarantee or show real causes of abuse.
The Real Amp-hour Capacity is viewable and measurable in the battery history for every discharge throughout its lifetime.