Lithium and alkaline batteries provide portable power that keeps our modern world running. But whether you need long-lasting energy for a multi-day backpacking trip or just a quick battery swap for the TV remote, understanding the differences between lithium and alkaline can help you choose the right option.
This in-depth guide examines lithium vs alkaline batteries across all key performance factors – rechargeability, lifespan, power delivery, customization, cost, and more. Read on for stats, expert perspectives on innovations in battery tech, plus safety tips and product recommendations.
A Peek Inside Battery Composition
First, a quick battery anatomy primer. Batteries convert stored chemical energy into usable electric current to power devices. At their core, all batteries contain:
A positively charged cathode. This electrode accepts electrons during discharge. Cathode materials determine battery voltage and capacity.
A negatively charged anode. The anode supplies electrons to the cathode through the circuit during discharge.
An electrolyte. This conductive medium connects the cathode and anode, allowing ion exchange. Electrolytes are typically liquid, paste or solid polymers.
Separators block physical contact between the anode and cathode while still enabling ion transfer via the electrolyte.
When the circuit connects, electrons flow from anode to cathode through the device being powered while ions shuttle through the electrolyte.
Li-ion versus Li-metal
Not all lithium batteries are created equal. Lithium ion batteries use intercalated lithium – ions bonded within carbon anodes and various lithiated metal oxide cathodes like lithium cobalt oxide (LiCoO2).
Meanwhile lithium (or lithium metal) batteries utilize metallic lithium anodes and non-aqueous liquid electrolytes with lithium salts.
Lithium metal batteries offer higher energy density but present fire risks if dendrites form during recharging. More on battery safety later!
| Parameter | Lithium Ion | Lithium Metal |
|---|---|---|
| Anode | Carbon | Lithium metal |
| Cathode | LiCoO2, LiMn2O4 etc. | Transition metal oxides |
| Electrolyte | Lithium salts in organic solvents | Non-aqueous liquid with Li salts |
| Energy Density | 100-265 Wh/kg | >400 Wh/kg theoretical |
| Cycle life | 500-1000 cycles | <500 cycles |
| Safety | More stable | Flammable if dendrites form during recharging |
Now let‘s stack alkaline batteries against these lithium technologies.
Charging Cycles: Alkaline Falls Short
A major limitation of alkaline batteries is that most are not rechargeable. They‘re designed for single use before being recycled or tossed out.
Rechargeable alkaline battery technology exists but maxes out around 50 cycles. In contrast, most mass market lithium ion batteries last 300-500 full discharge/charge cycles.
Premium lithium ion cells with cathodes using phosphate rather than cobalt now achieve 600-1,000 lifecycles. Specialty lithium batteries made for biomedical devices or aerospace can retain 80% capacity for 3,000+ cycles.
Dendrite formation during recharging causes lithium metal batteries to top out around 500 cycles before fire risks increase. New electrolyte formulations currently in R&D aim to address this roadblock.
Alkaline battery voltage drops steadily during discharge until a steep final plunge (Credit: Battery Guy)
The verdict? Lithium ion technology still reigns supreme on rechargability – offering 100-200 times more charging cycles versus alkaline batteries over a battery‘s lifespan.
Lifespan: Lithium Batteries Go the Distance
Closely related to recharge cycles is overall battery lifespan, whether used intermittently or stored for later use.
Lithium ion cells typically retain 70-80% of original capacity for 3-5 years with gradual performance decline over 10-15 years. Premium lithium batteries maintain capacity above 60% for 8 years or more.
Alkaline batteries fare more poorly over time. Voltage begins dropping within 12-24 months whether you use them or not. 80% capacity lasts just 4-5 years during storage. After a decade voltage drops so low that alkaline batteries won‘t adequately power devices.
The bottom line? Choose lithium batteries for devices used infrequently or emergency preparedness kits that demand years-long readiness.
Alkaline works best for low-to-medium drain items used at least occasionally each year before the slow self-discharge starts accumulation.
Power and Voltage: Lithium Pulls Ahead
Two key metrics indicate how much electrical power a battery can deliver:
Voltage measures available electrical potential difference between two points in a circuit – in this case a battery‘s cathode and anode terminals.
Power density describes capacity relative to the battery‘s mass or volume – how much total energy stored inside compared to overall size and weight.
Alkaline batteries provide a steady 1.5V as you drain them, slowly dropping to 0.8-1V when the battery runs out of juice.
In contrast, lithium ion cells operate from 3V to 3.7V, more than double the electrical power potential. Their flatter discharge curve delivers that higher voltage for 80-90% of the rated capacity before it drops. Lithium batteries also offer far higher energy density:
- Lithium Ion: 100-265 Wh/kg
- Lithium Metal: >250 Wh/kg up to ~500 Wh/kg theoretical
- Alkaline: 50-80 Wh/kg
So for electronics like digital cameras, tablets or two-way radios demanding sustained power in a compact form factor, lithium batteries deliver. They extract 2-3 times the electrical work from the same battery weight or volume.
Cost Comparison
Upfront price presents the most obvious disadvantage of lithium batteries compared to single use alkaline cells. Cost varies widely based on:
- Battery size and type (cylindrical, prismatic, coin, etc.)
- Cathode chemistry
- Quality tier
- Quantity purchased
But generally expect to pay 2-5 times more per lithium battery compared to an alkaline equivalent.
Let‘s run cost per usage numbers for two examples:
AAA batteries to power a digital camera that takes 500 photos per charge:
- Photoicon Alkaline: $8 for 12 batteries = $0.67 per 500 photos
- Amazon Basics Lithium: $12 for 8 batteries = $1.50 per 500 photos
Four AA batteries provide 10 hours of power for a tablet computer:
- Duracell Alkaline: $8 for 12 batteries = $0.27 per hour
- Energizer Lithium: $16 for 4 batteries = $4 per hour
However, the ability to recharge lithium cells hundreds of times before replacement ultimately justifies the steeper upfront cost and delivers savings over years of use.
Customization Options: Lithium Leads
While alkaline batteries come in standardized dimensions, lithium cells can be custom manufactured for specialty applications. This allows flexibility to power devices with odd or constrained internal geometries.
Custom lithium solutions cost more than off-the-shelf batteries but enable innovations. As examples:
- Thin curved batteries conforming precisely to smartwatch or fitness band form factors
- Low temperature lithium batteries for satellite electronics
- High current density lithium coin cells for medical implants
So if you need unique battery shapes, capacities, multi-cell configurations or advanced performance – consider custom lithium cells.
Comparative Safety: Handling Precautions
Both lithium and alkaline batteries require reasonable precautions during handling, charging, storage and disposal to prevent leaks, explosions or fires and environmental impact. However, the stakes are higher with lithium chemistry.
Alkaline batteries rarely burn unless deliberately incinerated or severely overheated to extremely high temperatures. Defective lithium-ion batteries become a flammable risk – if crushed, punctured, overheated or overcharged during improper charging. The most hazardous scenario involves internal short circuits triggering thermal runway.
These failures most often stem from battery manufacturing defects or improper use rather than inherent chemistry risks. Still exercise due diligence with lithium-powered consumer electronics especially when charging overnight. Also take care to avoid crushing or piercing during storage or transport.
Water contamination creates another danger – triggering potential thermal runaway or hydrogen fluoride gas release. This gas causes lung, skin and eye damage.
Follow basic precautions and lithium-ion batteries remain reasonably safe for consumers. Their extra power density does demand extra care during handling. Dispose of all expired batteries properly rather than tossing into normal trash.
Now let‘s glimpse over the horizon at emerging innovations that promise to transform lithium and alkaline battery technology…
Future Gazing: Battery Tech Breakthroughs
Incremental engineering advances constantly enhance lithium battery safety, lifespans, charging speeds and energy density. Meanwhile radical R&D progresses on step change technologies:
Solid State Batteries replace liquid electrolytes with solid ceramic or polymers. This prevents dendrite formation enabling lithium metal anodes rather than lower density graphite. Solid electrolytes also enable thinner cells. Startup Factorial Energy promises 50% increased range for electric vehicles via solid state lithium metal tech. Commercial production ramps in 2025.
Lithium-sulfur batteries offer 5-10X higher capacity thanks oxides. Sulfur cathodes store more lithium ions using abundant, eco-friendly sulfur. 500 Wh/kg energy density approaches gasoline equivalence. But sulfur dissolution during cycling hampers lifespan currently limited to 50-100 cycles. Solutions are maturing via additives. Oxis Energy expects lithium-sulfur EV batteries by 2025 with 600 mile range.
Rechargeable alkaline manganese batteries offer an eco-friendlier alternative by eliminating rare earth metals. But energy density and recharge cycles still lag lithium ion. Continuous research targets performance improvements.
Recommendations: Choosing What‘s Right for You
Weigh your portable power needs – runtime, longevity, reuse, voltage – then balance against budget when choosing between lithium vs alkaline batteries.
Lithium Batteries Excel For:
- High drain digital electronics – cameras, tablets, handheld tools
- Minimizing cost over cumulative years of use
- Backup and emergency preparedness kits
- Custom batteries sized for unusual electronics
- Peak performer electronics like drones
Our top lithium battery pick?
Energizer Ultimate Lithium AA Batteries have become my go-to for any application demanding ultimate longevity like LED flashlights used for off-grid emergencies. At just $1 per battery when purchased in bulk, they offer good value too.
Alkaline AA and AAA Economize for:
- TV remote controls, wall clocks
- Toys and wireless game controllers
- Low energy appliances like smoke detectors
- Cost sensitive household battery needs
For alkaline batteries, I stick with the economical Amazon Basics option whenever bulk matters more than absolute longevity per battery. Their 48 pack goes for just over $0.30 per cell.
Conclusion: Choose What Best Fits Your Needs
While no clear universal "winner" emerges between lithium and alkaline batteries, understanding key trade-offs allows best matching to personal preferences and use cases.
Lithium battery technology holds clear advantages for powering performance-driven electronics with sustained energy needs thanks to substantial leads in reusability, energy density and voltage.
Alkaline cells retain a cost advantage for intermittent low drain uses – and safer chemistry better suited to typical household applications.
Continued engineering iterations will extend lithium battery capabilities over coming years. But good old alkaline cells aren‘t disappearing anytime soon from the world‘s gadget drawers either.
Hopefully this guide gave you the essential data for choosing what type of portable power works best for your life!
