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BYD’s New Blade Battery Set to Redefine EV Safety Standards 

SHENZHEN, China, March 29, 2020 /PRNewswire/ — Today, BYD officially announced the launch of the Blade Battery, a development set to mitigate concerns about battery safety in electric vehicles.

 

At an online launch event themed “The Blade Battery – Unsheathed to Safeguard the World”, Wang Chuanfu, BYD Chairman and President, said that the Blade Battery reflects BYD’s determination to resolve issues in battery safety while also redefining safety standards for the entire industry.

New-Blade-Battery

BYD highlighted a video of the Blade Battery successfully passing a nail penetration test, which is seen as the most rigorous way to test the thermal runaway of batteries due to its sheer difficulty. “In terms of battery safety and energy density, BYD’s Blade Battery has obvious advantages,” said Professor Ouyang Minggao, Member of the Chinese Academy of Sciences and Professor at Tsinghua University.

 

The Blade Battery has been developed by BYD over the past several years. The singular cells are arranged together in an array and then inserted into a battery pack. Due to its optimized battery pack structure, the space utilization of the battery pack is increased by over 50% compared to conventional lithium iron phosphate block batteries.

 

While undergoing nail penetration tests, the Blade Battery emitted neither smoke nor fire after being penetrated, and its surface temperature only reached 30 to 60°C. Under the same conditions, a ternary lithium battery exceeded 500°C and violently burned, and while a conventional lithium iron phosphate block battery did not openly emit flames or smoke, its surface temperature reached dangerous temperatures of 200 to 400°C. This implies that EVs equipped with the Blade Battery would be far less susceptible to catching fire – even when they are severely damaged.

 

The Blade Battery also passed other extreme test conditions, such as being crushed, bent, being heated in a furnace to 300°C and overcharged by 260%. None of these resulted in a fire or explosion.

 

He Long, Vice President of BYD and Chairman of FinDreams Battery Co., Ltd., covered four distinct advantages of the Blade Battery including a high starting temperature for exothermic reactions, slow heat release and low heat generation, as well as its ability to not release oxygen during breakdowns or easily catch fire.

 

In the past few years, many EV manufacturers have fallen into a competition for ever-greater cruising range. When the range becomes the prime factor to consider, this focus is then transferred to power battery makers, leading to unreasonable pursuits of “energy density” in the battery industry. It is due to this unpractical focus on “energy density” that safety has been sidelined from power battery development. BYD’s Blade Battery aims to bring battery safety back to the forefront, a redirection from the industry’s tenuous focus on this crucial aspect.

 

“Today, many vehicle brands are in discussion with us about partnerships based on the technology of the Blade Battery,” said He Long. He added that BYD will gladly share and work with global partners to achieve mutually beneficial outcomes for all industry players.

 

The Han EV, BYD’s flagship sedan model slated for launch this June, will come equipped with the Blade Battery. The new model will lead the brand’s Dynasty Family, boasting a cruising range of 605 kilometers and an acceleration of 0 to 100km/h in just 3.9 seconds.

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Marine Batteries Types, Charging, Wiring & Set Up

Boat-Battery

Marine batteries are designed specifically for use on a boat, with heavier plates and robust construction designed to withstand the vibration and pounding that can occur onboard any powerboat. For this reason, marine batteries are usually more expensive than automobile batteries, which can tempt some boat owners to purchase an auto battery instead of a marine battery. Don’t make that poor decision. A marine battery will last longer and be more reliable than an auto battery in a boat.

There are three basic types of marine batteries:

  • Marine Starting Batteries provide quick but powerful spurts of energy over short periods of time and are designed to start the engine and be rapidly recharged by the engine alternator. A starting battery should not be used for trolling motors or powering appliances.
  • Marine Deep Cycle Batteries are designed to discharge slowly over a long period of time and to withstand several hundred charging and discharging cycles. A deep cycle battery is a right choice for powering an electric trolling motor and other battery-powered accessories such as audio systems, a windlass, depth finders, fish locators, and appliances. Deep cycle batteries should not be substituted for starting batteries.
  • Marine Dual-Purpose Batteriescombine the performance of starting and deep cycle battery, and are a good choice on smaller when there’s no room for two batteries. While they’re able to perform the tasks of a starting battery and deep cycle battery, they’re not as efficient as separate batteries.

Boat Battery

Deep Cycle vs. Cranking

If you have an electric trolling motor, thruster, windlass, or other battery-powered accessories that draw larger amounts of current, you’ll want a separate deep cycle “house” battery for that purpose. A deep cycle battery is only meant to be used where high rates of discharging and re-charging occur often. A deep cycle battery is constructed differently than a cranking battery, with thicker, heavier plates. The longer, higher amperage requirements of trolling motors and windlasses, for example, would heat and distort the thinner plates of a normal cranking battery.

The cranking battery has more yet thinner plates to give a fast voltage spike to crank an engine but is not intended to maintain high power output for long periods. Yes, a deep cycle battery can be used to start your motor in a pinch, but a two- or three-battery system is highly recommended to separate the engine battery from the accessory (house) batteries.

The best way to be sure your battery is still good is to have it “load tested.” Most auto parts or battery specialty stores will load test your battery for free and tell you if it’s still serviceable. Just because it’s gone dead once or twice doesn’t necessarily mean it’s no good. The rest of your electrical and charging systems may need some attention as well, as something other than the battery itself may be the cause of the problem.

Replacing Your Boat’s Battery

Consult your boat owner’s manual or a marine dealer when replacing a marine battery, and be sure to buy a new battery that is a good match for your boat. Marine batteries are rated by their ampere hour rating, reverse capacity, and marine cranking amps. When shopping for a deep cycle battery, you’ll want to pay the most attention to the ampere hour rating and reserve capacity. For starting batteries, focus primarily on the marine cranking amps. Consult all three rankings when searching for a dual-purpose battery.

If you add electrical accessories to your boat, you may need to upgrade to a battery with a higher amp-hour rating, especially if you spend a lot of time trolling with the engine at a very low speed (which results in less charging power from the alternator) or you spend a lot of time beached or at anchor while using accessories like the audio system.

Charging a Marine Battery

Most of us understand that when we are buying a new or used boat, the batteries supplied may not necessarily be top-of-the-line. If they seem to do the job, we don’t think much about them. But in the warmer climates everyday heat is a major enemy of batteries and can shorten their life considerably. In areas of the country that force us to put boats in storage for the winter, how the battery is cared for during this period is also critical to increasing life expectancy.

It’s best to keep batteries on a regulated “trickle” charger to maintain charge while not in use. A battery that is not charged (and kept charged) can freeze in cold temperatures and a cracked case is the likely result.  A battery is like a lot of things in life—use it or lose it! A car battery will typically last longer than a boat battery because the car is used regularly and the battery stays charged. When it comes to boats, the old adage of a battery’s life being two years is pretty well on the mark. You’ll usually get a heads-up when it’s about to give up on you, with the warning being a “dead” battery one morning or a bit slower cranking speed than you’re used to. You plug in the charger, the battery miraculously comes to life, and you’re off on your trip. You may think the light was left on, or that the radio memory pulled the voltage down. The reality may be that the battery is sulfating, plates are warped, and it no longer takes or holds a charge like it once did.

Tips for Avoiding Battery Problems

  • Secure the marine battery with a good battery tray, which should have a base that is screwed or bolted to the boat and either a rigid bracket or a locking strap to hold it to the base. You don’t want the battery banging around in rough water.
  • Frequently check the battery terminal connections to make sure they are snug and free of corrosion. Replace the wing nuts often found on marine batteries with nylon locking nuts, which are much less likely to come loose.
  • If you use the boat infrequently, use a maintenance-type battery charger to keep the battery fully charged between outings.
  • Before off-season storage completely charge the batteries then disconnect the terminals so nothing can draw the battery down. If there’s power available at your storage site, keep the batteries on a battery maintainer/charger through the off-season to continually maintain your batteries. Otherwise, remove the batteries from the boat and store them where they can be connected to a maintenance charger.
  • Install a cover or “boot” over the top of the positive battery terminal, if one was not installed by the boat builder, even if the battery is in a covered box. The boot prevents sparks and arcing and possible explosion if, for instance, a tool is dropped on the terminal.

Bottom line? Keep your batteries charged, keep the terminals clean, and by all means get out in the boat and “exercise” your electrical system as often as you can!

 

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Battery pole piece spot welding

12v 100ah lifepo4

Battery pole piece spot welding machine work principle:

12v 100ah lifepo4

Battery pole piece spot welder use of ultrasonic metal welding principle, ultrasonic metal welding should be classified as don’t need preheating welding. Oxidation surface is the great friction welding which division, and at the same time two parts are pressed together. This program let two materials to produce the atom so close to the action. Far below melting point relatively slight increase of temperature in the welding process is not important factors. At the same time, because the basic material not liquefied, so there is no microstructure changes, also will not damage to internal structure. Ultrasonic cell metal special welding machine is suitable for: aluminum + nickel, nickel and copper foil, aluminum + aluminum foil, multilayer copper foil, multi-layer aluminum foil, multilayer copper nets, multilayer aluminum mesh, aluminum plate + aluminum strip, aluminum nickel composite belt + aluminium plate, aluminum shell bottom + ni-clad-al strip double point welding; And with nickel and copper foil, nickel band and aluminum belt, aluminium strip and aluminum foil, aluminum band and aluminum cover, aluminum shell and ni-clad-al strip of the material such as the single point, multipoint, single, multi-layer, square, form and process of welding. Features suitable for battery, hardware, electrical appliances and motor industry.

Battery pole piece spot welder features:

  1.  due to the bench ultrasonic cell metal welding machine machine 80% use import parts and components, to ensure low failure rate and machine section structure design is reasonable;
  2.  ultrasonic lithium ion battery metal welding machine of welding mould can according to different application fast and convenient to change;
  3.  ultrasonic cell copper foil nickel sheet welding machine with German import piezoelectric ceramic transducer, stable and durable;
  4.  miniature ultrasonic power battery cover sheet welding machine operation easy, built-in electronic protection circuit, the use of safe,
  5. independent research and development, and the ultrasonic cell metal welding mould and welding head, reached the advanced world level, reduce the enterprise cost;
  6. ultrasonic nimh battery pole piece very ear welding machine used for the same kind of metal welding, to foreign non-ferrous metal implement single point or multipoint welding, especially copper aluminum nickel sheet, line, take welding.

Battery pole piece spot welder advantages:

The machine use desktop integration design, reasonable structure, beautiful appearance, Vertical motion, positioning accuracy is high, the welding effect is good; Welding head and the integral design of the mould can ensure the consistency of the welding effect, and extend the welding head life; New mould manufacture and maintenance cost is low, the welding of high efficiency; Advance to set the energy, time of welding parameters, constant welding parameter to ensure the welding quality. The operation is simple, convenient assembly, easy maintenance, can according to the customer the production needs of customized; Combined with quality control system for automatic process monitoring, without professional technician, on-site staff need to accept a day of training that will operate. Features suitable for wire and guide piece of the connections between, lithium nimh battery electric etc with nickel sheet alloy plate ni-clad-al strip connection, household electric parts and wire welding, all kinds of high or low conductivity metal and alloy, etc.

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Tesla May Soon Have a Battery That Can Last a Million Miles

Elon Musk promised Tesla would soon have a million-mile battery, more than double what drivers can expect today. A new paper suggests he wasn’t exaggerating.

 

Hybrid Car Battery

LAST APRIL, ELON Musk promised that Tesla would soon be able to power its electric cars for more than 1 million miles over the course of their lifespan. At the time, the claim seemed a bit much. That’s more than double the mileage Tesla owners can expect to get out of their car’s current battery packs, which are already well beyond the operational range of most other EV batteries. It just didn’t seem real—except now it appears that it is.

 

Earlier this month, a group of battery researchers at Dalhousie University, which has an exclusive agreement with Tesla, published a paper in The Journal of the Electrochemical Society describing a lithium-ion battery that “should be able to power an electric vehicle for over 1 million miles” while losing less than 10 percent of its energy capacity during its lifetime.

 

Led by physicist Jeff Dahn, one of the world’s foremost lithium-ion researchers, the Dalhousie group showed that its battery significantly outperforms any similar lithium-ion battery previously reported. They noted their battery could be especially useful for self-driving robotaxis and long-haul electric trucks, two products Tesla is developing.

 

What’s interesting, though, is that the authors don’t herald the results as a breakthrough. Rather, they present it as a benchmark for other battery researchers. And they don’t skimp on the specifics.

 

“Full details of these cells including electrode compositions, electrode loadings, electrolyte compositions, additives used, etc. have been provided,” Dahn and his colleagues wrote in the paper. “This has been done so that others can recreate these cells and use them as benchmarks for their own R+D efforts.”

 

Within the EV industry, battery chemistries are a closely guarded secret. So why would Dahn’s research group, which signed its exclusive partnership with Tesla in 2016, give away the recipe for such a seemingly singular battery? According to a former member of Dahn’s team, the likely answer is that Tesla already has at least one proprietary battery chemistry that outperforms what’s described in the benchmark paper. Indeed, shortly after the paper came out, Tesla received a patent for a lithium-ion battery that is remarkably similar to the one described in the paper. Dahn, who declined to comment for this article, is listed as one of its inventors.

 

The lithium-ion batteries described in the paper use lithium nickel manganese cobalt oxide, or NMC, for the battery’s positive electrode (cathode) and artificial graphite for its negative electrode (anode). The electrolyte, which ferries lithium ions between the electrode terminals, consists of a lithium salt blended with other compounds.

 

NMC/graphite chemistries have long been known to increase the energy density and lifespan of lithium-ion batteries. (Almost all electric cars, including the Nissan Leaf and Chevy Bolt, use NMC chemistries in their batteries, but notably not Tesla.) The blend of electrolyte and additives is what ends up being the subject of trade secrets. But even those materials, as described in the paper, were well known in the industry. In other words, says Matt Lacey, a lithium-ion battery expert at the Scania Group who was not involved in the research, “there is nothing in the secret sauce that was secret!”

 

Instead, Dahn’s team achieved its huge performance boosts through lots and lots of optimizing of those familiar ingredients, and by tweaking the nanostructure of the battery’s cathode. Instead of using many smaller NMC crystals as the cathode, this battery relies on larger crystals. Lin Ma, a former PhD student in Dahn’s lab who was instrumental in developing the cathode design, says this “single-crystal” nanostructure is less likely to develop cracks when a battery is charging. Cracks in the cathode material cause a decrease in the lifetime and performance of the battery.

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The Low-Down On Low Speed Vehicles (LSV)

When people wanted something roomier than a station wagon but not as commercial-looking as a van, the auto industry gave us minivans. Then when people wanted something sportier than minivans but not as workmanlike as pickup…

Read more
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Save Thousands On Medical Batteries Each Year

Reports from the Energy Storage Research Program at DOE have found that “every year roughly one-million usable lithium-ion batteries are sent for recycling”. Knowing when to replace a battery is an ongoing concern and date-stamping serves as only a partial and imperfect solution. It is important to understand and acknowledge the fact that batteries do not fail suddenly, but rather they follow a predicted decline in capacity losing performance over time. Battery life is governed by usage, not time.

 

A new battery is rated at a nominal capacity of 100%. As the battery ages, the reserve capacity drops and the battery eventually needs replacing when the reserve capacity falls below a certain level to be defined depending on the application of a battery-powered medical device.

Nickel-based batteries provide about three-years of service; Li-on five. Storage characteristics have also improved. However, under-usage in healthcare is more common than ever, and bio-medical technicians have discovered that many medical batteries that are recycled still have a capacity of above 90%, leading to millions of unchecked batteries being discarded every year.

 

The date-stamping approach to batteries has several serious flaws:

It does not detect a damaged or prematurely faded battery. Batteries that are used regularly may fade before the expiry date listed on the stamp.

Through this approach, it is also often neglected that even batteries held in storage and are not in use, lose capacity over time.

It is a costly procedure as it does not allow for full battery service life to be used, resulting in most batteries in this system being replaced after less than half of their useful life is still intact. Li-on batteries, for example, often last 2-3 times longer than the date stamp mandates, but also have higher purchase prices making premature disposal even more costly.

 

By replacing the arguably outdated approach to battery replacement, with a greener, more reliable approach, the future of battery management in healthcare will be increasingly optimized.

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Learn How to Arrange Batteries to Increase Voltage or Gain Higher Capacity

Batteries achieve the desired operating voltage by connecting several cells in series; each cell adds its voltage potential to derive at the total terminal voltage. Some packs may consist of a combination of series and parallel connections. Laptop batteries commonly have four 3.6V Li-ion cells in series to achieve a nominal voltage 14.4V and two in parallel to boost the capacity from 2,400mAh to 4,800mAh. Such a configuration is called 4s2p, meaning four cells in series and two in parallel.

 

It is important to use the same battery type with equal voltage and capacity (Ah) and never to mix different makes and sizes. A weaker cell would cause an imbalance, as a battery is only as strong as the weakest link in the chain.

 

Single Cell Applications

The single-cell configuration is the simplest battery pack; the cell does not need matching and the protection circuit on a small Li-ion cell can be kept simple. Typical examples are mobile phones and tablets with one 3.60V Li-ion cell. Other uses of a single cell are wall clocks, which typically use a 1.5V alkaline cell, wristwatches and memory backup, most of which are very low power applications.

 

Series Connection

Portable equipment needing higher voltages use battery packs with two or more cells connected in series.

Figure 2: Series connection of four cells (4s).
Adding cells in a string increases the voltage; the capacity remains the same.

 

High voltage batteries keep the conductor size small. Cordless power tools run on 12V and 18V batteries; high-end models use 24V and 36V. Most e-bikes come with 36V Li-ion, some are 48V. The car industry wanted to increase the starter battery from 12V (14V) to 36V, better known as 42V, by placing 18 lead acid cells in series.

Some mild hybrid cars run on 48V Li-ion and use DC-DC conversion to 12V for the electrical system.

 

 

Parallel Connection

If higher currents are needed and larger cells are not available or do not fit the design constraint, one or more cells can be connected in parallel. Most battery chemistries allow parallel configurations with little side effect.

Figure 4: Parallel connection of four cells (4p).

With parallel cells, capacity in Ah and runtime increases while the voltage stays the same.

 

Series/parallel Connection

The series/parallel configuration shown in Figure 6 enables design flexibility and achieves the desired voltage and current ratings with a standard cell size. The total power is the product of voltage-times-current; four 3.6V (nominal) cells multiplied by 3,400mAh produce 12.24Wh. Four 18650 Energy Cells of 3,400mAh each can be connected in series and parallel as shown to get 7.2V nominal and 12.24Wh. The slim cell allows flexible pack design but a protection circuit is needed.

Figure 6: Series/ parallel connection of four cells (2s2p).

This configuration provides maximum design flexibility. Paralleling the cells helps in voltage management.

 

Safety devices in Series and Parallel Connection

Positive Temperature Coefficient Switches (PTC) and Charge Interrupt Devices (CID) protect the battery from overcurrent and excessive pressure. While recommended for safety in a smaller 2- or 3-cell pack with serial and parallel configuration, these protection devices are often being omitted in larger multi-cell batteries, such as those for power tool.

 

 Simple Guidelines for Using Household Primary Batteries

  • Keep the battery contacts clean. A four-cell configuration has eight contacts and each contact adds resistance (cell to holder and holder to next cell).
  • Never mix batteries; replace all cells when weak. The overall performance is only as good as the weakest link in the chain.
  • Observe polarity. A reversed cell subtracts rather than adds to the cell voltage.
  • Remove batteries from the equipment when no longer in use to prevent leakage and corrosion. This is especially important with zinc-carbon primary cells.
  • Do not store loose cells in a metal box. Place individual cells in small plastic bags to prevent an electrical short. Do not carry loose cells in your pockets.
  • Keep batteries away from small children. In addition to being a choking hazard, the current-flow of the battery can ulcerate the stomach wall if swallowed. The battery can also rupture and cause poisoning.
  • Do not recharge non-rechargeable batteries; hydrogen buildup can lead to an explosion. ·Perform experimental charging only under supervision.

 

Simple Guidelines for Using Secondary Batteries

  • Observe polarity when charging a secondary cell. Reversed polarity can cause an electrical short, leading to a hazardous condition.
  • Remove fully charged batteries from the charger. A consumer charger may not apply the correct trickle charge when fully charged and the cell can overheat.
  • Charge only at room temperature.
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LiFePO4 Care Guide: Looking After Your Lithium Batteries

LOOKING-AFTER-YOUR-LITHIUM-BATTERIES

LiFePO4 chemistry lithium cells have become popular for a range of applications in recent years due to being one of the most robust and long-lasting battery chemistries available. They will last ten years or more if cared for correctly. Please take a moment to read these tips to ensure you get the longest service from your battery investment.

 

Tip 1: Never over charge/discharge a cell!

The most common causes for premature failure of LiFePO4 cells are overcharging and over-discharging. Even a single occurrence can cause permanent damage to the cell, and such misuse voids the warranty. A Battery protection System is required to ensure it is not possible for any cell in your pack to go outside its nominal operating voltage range,

In the case of LiFePO4 chemistry, the absolute maximum is 4.2V per cell, though it is recommended that you charge to 3.5-3.6V per cell, there is less than 1% extra capacity between 3.5V and 4.2V.

Over charging causes heating within a cell and prolonged or extreme overcharging has the potential to cause a fire. EV Works Takes no responsibility for any damages caused as a result of a battery fire.

Over charging may occur as a result of.

  • Lack of a suitable battery protection system
  • Faulty of infective battery protection system
  • incorrect installation of the battery protection system

 

At the other end of the scale, over-discharging can also cause cell damage. The BMS must disconnect the load if any cells are approaching empty (less than 2.5V). Cells may suffer mild damage below 2.0V, but are usually recoverable. However, cells which get driven to negative voltages are damaged beyond recovery.

On 12v batteries the use of a low voltage cutoff takes the place of the BMS by preventing the overall battery voltage going under 11.5v no cell damage should occur. On the other end charging to no more than 14.2v no cell should be overcharged.

battery-test

Tip 2: Clean your terminals before installation

The terminals on top of the batteries are made from aluminium and copper, which over time builds up an oxide layer when exposed to air. Before installing your cell interconnectors and BMS modules, clean the battery terminals thoroughly with a wire brush to remove oxidation. If using bare copper cell interconnectors, these should be cleaned too. Removing the oxide layer will greatly improve conduction and reduce heat buildup at the terminal. (In extreme cases, heat buildup on terminals due to poor conduction has been known to melt the plastic around the terminals and damage BMS modules!)

 

Tip 3: Use the right terminal mounting hardware

Winston cells using M8 terminals (90Ah and up) should use 20mm long bolts. Cells with M6 terminals (60Ah and under) should use 15mm bolts. If in doubt, measure the thread depth in your cells and ensure that the bolts will get close to but not hit the bottom of the hole. From top to bottom you should have a spring washer, flat washer then the cell interconnector.

 

A week or so after installation, check that all your terminal bolts are still tight. Loose terminal bolts can cause high-resistance connections, robbing your EV of power and causing undue heat generation.

 

Tip 4: Charge frequently and shallower cycles

With lithium batteries, you will get longer cell life if you avoid very deep discharges. We recommend sticking to 70-80% DoD (Depth of Discharge) maximum except in emergencies.

Swollen Cells

Swelling will only occur if a cell has been over-discharged or in some cases overcharged. Swelling does not necessarily mean the cell is no longer usable though it will likely lose

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Do hybrid cars cause pollution？

Hybrid-car-battery

Eco-conscious drivers are buying hybrid cars and other fuel-efficient vehicles for their lower emissions. The combination of a smaller gasoline engine for power, an electric motor for fuel economy and the promise of so-called green driving have proven to be successful incentives for consumers looking to save money on fuel and do their part to help out the environment. But increased awareness about the environmental impact vehicles and vehicle parts have on the Earth has led drivers to shift their concern from fuel efficiency to something else entirely — hybrid car batteries.

 

The batteries in hybrid cars are responsible for the better fuel economy that’s become central to the technology. They power the electric motor, which typically propels a hybrid car at lower speeds. This puts less pressure on the gasoline engine and stretches out the amount of fuel a vehicle burns in between trips to the gas station.

 

But the chemical material that makes up all car batteries, whether it’s a conventional car or a hybrid, is typically toxic. Currently, there are far fewer hybrid cars on the road than conventional cars; however, concerns have been raised that if the number of hybrid cars increase, landfills will soon overflow with toxic batteries that are full of corrosive and carcinogenic materials.

 

There are three major types of batteries that companies use or are considering for use in hybrid cars: lead-acid, nickel-metal hydride (NiMH) and lithium-ion (Li-ion). By far, lead-acid is considered the most toxic of the three, and on top of that it’s also extremely heavy, reducing some of the fuel efficiency gains from the electric motor. Lead-acid is becoming less of a contender in the hybrid car battery market and is being replaced by nickel-metal hydride. Nickel is less toxic than lead, but it’s not without its own problems — it’s potentially carcinogenic and the mining process is considered hazardous. Since they’re the least toxic, many consider lithium-ion batteries to be the next step for hybrid car batteries. In fact, car companies are investing millions of dollars in research for a working hybrid car battery that uses the same kind of power currently found in laptops and MP3 players.

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New Lithium-Based Battery Design Makes Use of Greenhouse Gas

TOPICS:Battery TechnologyCarbon DioxideGreen TechnologyMITSustainability
By DAVID L. CHANDLER, MIT NEWS OFFICE SEPTEMBER 22, 2018

This scanning electron microscope image shows the carbon cathode of a carbon-dioxide-based battery made by MIT researchers, after the battery was discharged. It shows the buildup of carbon compounds on the surface, composed of carbonate material that could be derived from power plant emissions, compared to the original pristine surface (inset). Courtesy of the researchers

New lithium-based battery could make use of greenhouse gas before it ever gets into the atmosphere.

A new type of battery developed by researchers at MIT could be made partly from carbon dioxide captured from power plants. Rather than attempting to convert carbon dioxide to specialized chemicals using metal catalysts, which is currently highly challenging, this battery could continuously convert carbon dioxide into a solid mineral carbonate as it discharges.

While still based on early-stage research and far from commercial deployment, the new battery formulation could open up new avenues for tailoring electrochemical carbon dioxide conversion reactions, which may ultimately help reduce the emission of the greenhouse gas to the atmosphere.

The battery is made from lithium metal, carbon, and an electrolyte that the researchers designed. The findings are described today in the journal Joule, in a paper by assistant professor of mechanical engineering Betar Gallant, doctoral student Aliza Khurram, and postdoc Mingfu He.

Currently, power plants equipped with carbon capture systems generally use up to 30 percent of the electricity they generate just to power the capture, release, and storage of carbon dioxide. Anything that can reduce the cost of that capture process, or that can result in an end product that has value, could significantly change the economics of such systems, the researchers say.

However, “carbon dioxide is not very reactive,” Gallant explains, so “trying to find new reaction pathways is important.” Generally, the only way to get carbon dioxide to exhibit significant activity under electrochemical conditions is with large energy inputs in the form of high voltages, which can be an expensive and inefficient process. Ideally, the gas would undergo reactions that produce something worthwhile, such as a useful chemical or a fuel. However, efforts at electrochemical conversion, usually conducted in water, remain hindered by high energy inputs and poor selectivity of the chemicals produced.

Gallant and her co-workers, whose expertise has to do with nonaqueous (not water-based) electrochemical reactions such as those that underlie lithium-based batteries, looked into whether carbon-dioxide-capture chemistry could be put to use to make carbon-dioxide-loaded electrolytes — one of the three essential parts of a battery — where the captured gas could then be used during the discharge of the battery to provide a power output.

This approach is different from releasing the carbon dioxide back to the gas phase for long-term storage, as is now used in carbon capture and sequestration, or CCS. That field generally looks at ways of capturing carbon dioxide from a power plant through a chemical absorption process and then either storing it in underground formations or chemically altering it into a fuel or a chemical feedstock.

Instead, this team developed a new approach that could potentially be used right in the power plant waste stream to make material for one of the main components of a battery.

While interest has grown recently in the development of lithium-carbon-dioxide batteries, which use the gas as a reactant during discharge, the low reactivity of carbon dioxide has typically required the use of metal catalysts. Not only are these expensive, but their function remains poorly understood, and reactions are difficult to control.

By incorporating the gas in a liquid state, however, Gallant and her co-workers found a way to achieve electrochemical carbon dioxide conversion using only a carbon electrode. The key is to preactivate the carbon dioxide by incorporating it into an amine solution.

“What we’ve shown for the first time is that this technique activates the carbon dioxide for more facile electrochemistry,” Gallant says. “These two chemistries — aqueous amines and nonaqueous battery electrolytes — are not normally used together, but we found that their combination imparts new and interesting behaviors that can increase the discharge voltage and allow for sustained conversion of carbon dioxide.”

They showed through a series of experiments that this approach does work, and can produce a lithium-carbon dioxide battery with voltage and capacity that are competitive with that of state-of-the-art lithium-gas batteries. Moreover, the amine acts as a molecular promoter that is not consumed in the reaction.

The key was developing the right electrolyte system, Khurram explains. In this initial proof-of-concept study, they decided to use a nonaqueous electrolyte because it would limit the available reaction pathways and therefore make it easier to characterize the reaction and determine its viability. The amine material they chose is currently used for CCS applications, but had not previously been applied to batteries.

This early system has not yet been optimized and will require further development, the researchers say. For one thing, the cycle life of the battery is limited to 10 charge-discharge cycles, so more research is needed to improve rechargeability and prevent degradation of the cell components. “Lithium-carbon dioxide batteries are years away” as a viable product, Gallant says, as this research covers just one of several needed advances to make them practical.

But the concept offers great potential, according to Gallant. Carbon capture is widely considered essential to meeting worldwide goals for reducing greenhouse gas emissions, but there are not yet proven, long-term ways of disposing of or using all the resulting carbon dioxide. Underground geological disposal is still the leading contender, but this approach remains somewhat unproven and may be limited in how much it can accommodate. It also requires extra energy for drilling and pumping.

The researchers are also investigating the possibility of developing a continuous-operation version of the process, which would use a steady stream of carbon dioxide under pressure with the amine material, rather than a preloaded supply the material, thus allowing it to deliver a steady power output as long as the battery is supplied with carbon dioxide. Ultimately, they hope to make this into an integrated system that will carry out both the capture of carbon dioxide from a power plant’s emissions stream, and its conversion into an electrochemical material that could then be used in batteries. “It’s one way to sequester it as a useful product,” Gallant says.

“It was interesting that Gallant and co-workers cleverly combined the prior knowledge from two different areas, metal-gas battery electrochemistry and carbon-dioxide capture chemistry, and succeeded in increasing both the energy density of the battery and the efficiency of the carbon-dioxide capture,” says Kisuk Kang, a professor at Seoul National University in South Korea, who was not associated with this research.

“Even though more precise understanding of the product formation from carbon dioxide may be needed in the future, this kind of interdisciplinary approach is very exciting and often offers unexpected results, as the authors elegantly demonstrated here,” Kang adds.

MIT’s Department of Mechanical Engineering provided support for the project.

Publication: Aliza Khurram, et al., “Tailoring the Discharge Reaction in Li-CO2 Batteries through Incorporation of CO2 Capture Chemistry,” Joule, 2018; doi:10.1016/j.joule.2018.09.002