26650 Battery dimensions. 26650 battery dimensions

Lithium Ion Flashlight Battery Sizes – What’s the Difference?

If you’re new to the flashlight world, you may be wondering about all these lithium ion batteries, what they are, what mAh stands for, what they’re good for, etc. So in this article, I want to talk about lithium-ion batteries including the different sizes of batteries and what kind of flashlight you should expect with each battery size. So let’s get started.

Lithium Ion Batteries for LED Flashlights

Flashlights can take all kinds of batteries from alkaline to Ni-MH to lithium. Some LED flashlights even have built-in batteries. However, most ultra bright flashlights are going to run on lithium-ion batteries. This is due to the high energy output these batteries have.

Lithium ion batteries are cost-effective due to the fact that they are rechargeable and provide a lot of power for an LED flashlight. So you can see higher outputs and longer run times with lithium-ion batteries.

What Does MaH Mean in Lithium Ion Batteries?

MAh stands for milliamps per hour and it’s a unit of electric charge. You’ll see a lot of lithium ion batteries advertising their mAh. Basically, the higher the mAh, the longer the run times are going to be. For example, there are 18650 batteries that have 2600 mAh and 3100 mAh.

26650, battery, dimensions

With a 3100 mAh, you’re going to be seeing a decently longer run time, up to 30% longer. Of course, you have to keep the voltage in mind as well when picking lithium-ion batteries. A lithium-ion battery with a lower voltage and higher milliamps won’t give you as much power as a battery with higher voltage and lower milliamps.

I recommend purchasing any 18650 battery from reputable brands such as Surefire, Olight, Nitecore, etc. There are brands out there whose batteries claim to have a higher mAh capacity than they actually do or are really cheap due to the fact that they’re unprotected so you want to look out for that.

Lithium-Ion Battery Sizes

Let’s talk about battery sizes. Lithium-ion batteries come in a range of sizes with batteries so small they fit into keychain flashlights. Some LED flashlights can take more than one kind of lithium ion battery which is good to know. But this will give you a general idea of the size of the different batteries. I’ll be talking about more common lithium ion batteries in LED flashlights, but there are more sizes than what I’m listing here.

26650 Li-Ion Battery

This is the biggest battery we’re going to be talking about here. This lithium ion battery is quite large and fits in flashlights that some people like to call soda can lights. These LED flashlights are usually not great for everyday carry due to their larger sizes, but they do provide extremely impressive outputs. I’ve seen 26650 batteries with a high mAh capacity of 5000, but there may be higher out there. The Klarus G20 LED flashlight has this battery.

21700 Li-Ion Battery

If you’ve been following my site, you may know that this is my new favorite battery. 21700 batteries are extremely compact but provide a lot of power behind them. You can find flashlights that use 21700 batteries in a variety of sizes from everyday carry to larger duty lights. The highest mAh capacity I’ve seen for a 21700 battery is 5000. I’ve made a big list of flashlights that use 21700 batteries if you’d like to check it out.

18650 Li-Ion Battery

An 18650 li-ion battery is still probably the most popular battery type for LED flashlights right now. They range in mAh capacities, but the highest I’ve seen would be 3500 mAh. They are smaller batteries, perfect for everyday carry flashlights, hand-held flashlights, tactical flashlights and a lot more.

A couple of flashlights that use this battery would be the Fenix E30R EDC flashlight and the Streamlight ProTac HPL tactical flashlight.

Here is a pretty cool 18650 battery on Amazon that has a built in micro USB charge port. This is newer technology and is great if your light does not have a recharge port or you don’t want to have to deal with a battery charger.

14500 Li-Ion Battery

A 14500 battery is roughly the same size as an AA battery. These are perfect for flashlights and everyday carry flashlights. The highest mAh I’ve seen for a 14500 battery would be 800. The Klarus XT1A runs on a 14500 battery.

16340 Li-Ion Battery

A 16340 battery is shorter than the 14500, but a bit wider. It is a very similar size to a CR123 lithium battery. Many everyday carry flashlights and flashlights use this battery. The highest mah capacity I’ve seen with a 16340 battery is 700. A high quality flashlight that use this particular battery is the Fenix E18R flashlight.

What Kind of Battery Should I Get for My LED Flashlight?

This all depends on the LED flashlight itself. Each battery listed here is a completely different size and not all batteries are going to be compatible with the same light. So some flashlights like the JetBeam KO-02 can take a 21700 battery and an 18650 battery or the Klarus XT11X which can take an 18650 battery or two 16340 batteries.

On the other hand, some lights can only stick with a single battery type. For example, the Klarus G20 can only stick with 26650 batteries. So I would recommend you first and foremost check out the manual and specs to see what batteries your flashlight needs.

Another aspect to consider would be button top vs. flat top. Depending on the flashlight you have, it may require either a button top battery or flat top battery. On top of that, I have seen many high-end tactical flashlights that can be a bit finicky about which batteries you use with it.

I recommend purchasing batteries from reputable brands because these will be more likely to work in high-end quality flashlights rather than some of the cheaper batteries you can find online.

Pros and Cons of Lithium-Ion Batteries

Before I end this article I want to briefly discuss the pros and cons of lithium ion batteries. Some of the great aspects of these batteries include the fact that they are rechargeable making them economical. Some lithium ion batteries come with a micro USB port or USB-C port so that you can actually charge the batteries directly.

Also, many LED flashlights are rechargeable which means you can charge the li-ion battery directly in the flashlight. Alternatively, you can use battery chargers.

Also, lithium ion batteries bring a lot of power to the light. You can expect higher outputs and longer run times with lithium-ion batteries than with pretty much any other battery.

One downside of lithium ion batteries is the fact that they don’t have the best shelf life. Lithium ion batteries drain slowly over time. This means that you need to charge them every couple months or so to make sure that the battery doesn’t go into deep discharge.

Deep discharge basically means that the battery is at such a low voltage it will not charge up and you can’t use the battery anymore.

26650, battery, dimensions

However, with so many USB rechargeable batteries and USB rechargeable flashlights, the benefits of using lithium-ion batteries far outweigh the downfalls. It’s extremely convenient to charge up these batteries. Lithium ion batteries are really a great choice for most tactical flashlights.

650 battery dimensions

Product Description:

LiFePO4 battery is Environmentally friendly, which will not destroy the ecological environment, also have no memory effects.

Have low internal resistance and high flat voltage characteristics during strong current discharge, which ensures a wider application field.

Provide long storage life with few limiting conditions. It offers problem-free charge after long storage, permitting to use in a wide range of applications.

Generally, what are Lithium-Ion Batteries? A. Lithium-ion batteries are rechargeable batteries in which lithium ions move from the anode to the cathode during discharging and back when charging. They are popular batteries for use in consumer electronics because they provide high energy density, possess no memory effect and have a slow loss of charge when not in use. These batteries come in a wide variety of shapes and sizes. Compared to lead-acid batteries, Lithium-ion batteries are lighter and provide a higher open circuit voltage, which allows for power transfer at lower currents. These batteries have the following characteristics:

Features of ionic Lithium-ion Deep Cycle Batteries:

Light weight, up to 80% less than a conventional, comparable energy storage lead-acid battery. Lasts 300-400% longer than lead-acid. Lower shelf discharge rate (2% vs. 5-8% /month). Drop-in replacement for your OEM battery. Expected 8-10 years of battery life. No explosive gasses during charging, no acid spills. Environmentally friendly, no lead or heavy metals. Safe to operate! The term “Lithium-ion” battery is a general term. There are many different chemistries for Lithium-Ion batteries including LiCoO2 (cylindrical cell), LiPo, and LiFePO4 (cylindrical/prismatic cell). Ionic mostly focuses on designing, manufacturing and marketing LiFePO4 batteries for its starter and deep cycle batteries.

What are LiFePO4 (Lithium Iron Phosphate) Batteries? A. Lithium Iron Phosphate (LiFePO4) batteries provide several advantages over traditional Lithium-ion batteries based on LiCoO2 chemistry. LiFePO4 batteries provide much higher specific capacity, superior thermal and chemical stability, enhance safety, improve cost performance, enhanced charge and discharge rates, enhanced cycle life and come in a compact, lightweight package. LiFePO4 batteries an offer a cycle life of over 2,000 charge cycles!

Why should I get a ionic’s lithium-ion “Deep Cycle” energy storage battery? A. Lithium-ion batteries provide multiple advantages over standard lead-acid batteries for energy storage use that we’ll outline below:

Substantially Lighter – Lithium-ion batteries are just a fraction of the weight of the original lead-acid battery. Powerful – Lithium-ion batteries operate at a higher voltage than standard lead-acid batteries, giving you faster engine speed for longer durations. Lead-acid batteries drop to just 12.5V when only 20% of the battery capacity is used, but lithium-ion batteries provide over 12.8V even when only 20% of the battery capacity is left. Low Self-Discharge Rate– Lead-acid batteries lose 4%-25% of their charge every month depending on the quality of the plates and separators used. If you leave a vehicle unattended for a month, the lead-acid battery might lose too much power and the vehicle might not start. On the other hand, our lithium battery chemistry loses less than 3% of charge per month; you can go for several months without having to worry. Environmental Friendly– Ionic batteries contain no toxic substances. There is no poisonous lead or corrosive sulfuric acid and as a result, no possible way for an explosive gassing event that is common with lead-acid batteries. In addition, there is no need to maintain acid levels or worry about venting like traditional lead-acid batteries do. The only maintenance that ionic batteries require is ensuring that the battery never drains beyond 80% to ensure optimal life. Long Lasting– Cheap lead-acid batteries usually only last 1 to 2 years while gel and AGM lead-acid batteries last 3-5 years with proper maintenance. However, ionic’s lithium-ion batteries can provide 8-10 years of use, easily exceeding the life of any lead-acid battery. Battery life depends purely on proper operation and maintenance, so use common-sense and ensure the battery does not drain beyond 80% discharge. If you are replacing a lead-acid battery in two years or less due to deep cycling damage, you will save money in the long run moving to a ionic lithium-ion Fast Recharging – ionic’s lithium-ion batteries can accept charge current at up to 5 times faster than a lead-acid battery. What’s more, the charge efficiency is about 75% for lead-acid in contrast to 97% for ionic’s lithium-ion battery. That means less energy is needed to charge and causes less strain on your alternator.

What advantages does ionic “Deep Cycle Batteries” have over other batteries? A. ionic utilizes the latest advancements in lithium-ion battery technology along with custom features to provide you with the best battery for your vehicle:

Internal Cell Balancing Circuit – ionic batteries have a micro-processor controlled internal cell balancing board in each of its batteries designed to maximize the performance of each cell in the batteries. Battery Management System (BMS) – ionic lithium-ion Smart batteries contain a solid state switch that controls temperature volatility. This switch prevents overcharging and discharging, improving the overall lifespan performance and safety of the batteries. Quality Engineering – ionic’s innovation laboratory prides itself on the design and construction of its batteries utilizing the highest quality components in all phases of design and construction. The ionic built-in intelligent components guarantee the safety and quality of each ionic product. Prismatic Cells – Cylindrical cells only come in certain sizes which limits the possible shapes and sizes of the starter battery case designs. As such, batteries fit for many vehicles may be poor, or impossible as they are too wide or too tall and create internal hot spots. Ionic prismatic cells on the other hand, are rectangular packages which can be freely designed and sized according to the size requirements of the battery case. As such, ionic offers perfect drop-in fit in most vehicles along with having better thermal management properties.

How does ionic’s “Deep Cycle” capacity (Ah) rating compare to lead-acid Ah ratings? A. Ionic’s “Deep Cycle” batteries have true lithium capacity rating at 1C discharge rate meaning a 12Ah “Deep Cycle” lithium-ion battery will be able to provide 12A for 1 hour. On the other hand, most lead-acid batteries have a 20hr or 25hr rating printed for its Ah capacity meaning the same 12Ah lead-acid battery discharging in 1 hour would typically only provide 6Ah of useable energy. Going below 50% DOD will damage a lead-acid battery, even if they claim to be a deep discharge battery. Thus a 12Ah lithium battery would perform closer to a 48Ah lead-acid battery rating for higher discharge currents and life performance. Ionic’s lithium-ion batteries have 1/3 the internal resistance of a similar capacity lead-acid battery and they can be safely discharged to 90% DOD. Lead-acid internal resistance rises as they are discharged; the actual capacity which can be used may be as little as 20% of the mfg. rating. Discharging in excess will damage the lead-acid battery. Ionic’s lithium-ion batteries hold a higher voltage during discharge.

650, 3.2V, 3300 mAh, 2C LFP Cells (4 pcs)

The Bioenno Power 26650, 3.2V, 3300 mAh LiFePO4 cells are excellent for a variety of applications including for assembling a variety of LiFePO4 battery packs. These cells provide 2C maximum continuous discharge current. The cells are sold in a pack of 4. Please note that these cells must be assembled in combination with a PCM/BMS into a battery pack by qualified users. The cells are not intended for use without protection.

Rated Capacity: 3300 mAhNominal Voltage: 3.2VDCCharging Voltage: 3.65VDCInternal Impedance: 40 milli-ohmsStandard Charge: Constant Current at 0.2C, Constant Voltage at 3.65 VDC, 0.01C cut-offStandard Discharge: Constant Current at 0.2C, Ending Voltage: 2.0VDCMaximum Continuous Charge Current: 1CMaximum Continuous Discharge Current: 2COperation Temperature: Charging. 0 to 45 deg C; Discharging.20 deg C to 60 deg CStorage Temperature Range:.20 deg C to 25 deg CCell Dimensions: 65 mm x 26 mm (Height x Diameter)

Shipping: Standard Returns/Exchange: 30 Days Warranty: 2 Years Standard Lithium Iron Phosphate Battery Warranty

Contact Us

For Sales Team: sale@bioennopower.com Toll Free: (888) 336-7864(888) 834-1986 (714) 234-7363 Fax Number: (714) 988-4223

For Technical Support (email only): sale@bioennopower.com

OFFICE VISIT BY APPOINTMENT ONLY Bioenno Power / Bioenno Tech LLC 3657 W. McFadden Ave. Santa Ana, California 92704 USA

Specification of A123 ANR26650 26650 LiFePO4 Battery Cell

A123s high-performance Nanophosphate® lithium iron phosphate (LiFePO4) battery technology delivers high power and energy density combined with excellent safety performance and extensive life cycling in a lighter weight, more compact package. The cells have low capacity loss and impedance growth over time as well as high usable energy over a wide state of charge (SOC) range, allowing our systems to meet end-of-life power and energy requirements with minimal pack oversizing.

Key Features and benefits

-Excellent abuse tolerance and superior cycle life from A123’s patented Nanophosphate lithium ion Chemistry.High power with over 2,600W/kg and 5,800 W/L, 10 seconds, 50%SOC.High usable energy over a wide state of charge (SOC) range



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