Battery and Charger Buying Guide 2020
This is a 2020 update for the battery and charger buying guide for light painting photographers. The previous article was written in 2018. There have been many updates in this edition.
Most light painter’s first flashlights are based on AAA, AA, and less commonly C, D, and 9V size batteries. These use non-rechargeable Alkaline, Zinc-chloride (Heavy Duty), Lithium, or rechargeable NiCd and NiMH batteries. These all have a max voltage of approximately 1.5V, apart from 9V batteries. Compared to li-ion batteries, these are generally very safe, and easy to purchase.
Alkaline batteries generally have good capacity, and are widely available almost everywhere. As they are not rechargeable, they are quite wasteful. Alkaline batteries can also leak, especially if they are left is a discharged state for a long time. Heavy Duty (Zinc-chloride) batteries are a cheaper alternative but will only last a few minutes in a good flashlight.
Lithium batteries (such as Energizer Ultimate Lithium) typically last twice as long as good Alkaline or NiMH batteries, but also cost more than twice the price of Alkaline. As they are not rechargeable, I would only really recommend them for use in extreme temperatures (-40C to +60C) or if you will have no access to power supply for a while.
For AAA/AA batteries I would recommend using rechargeable batteries. NiCd rechargeables are outdated, low capacity and best avoided. It is recommended to use low self discharge (LSD) NiMH batteries. The best examples of these for AAA and AA size are all made by FDK in Japan under various brand names:
1. Ikea Ladda batteries (white) – same as Eneloop Pro, but far cheaper.
2. Panasonic Eneloop Pro (only made in Japan versions)
3. Panasonic Eneloop (only made in Japan versions)
4. Fujitsu Ready To Use
Many NiMH chargers are “dumb” timer based and can overcook batteries. Thus it is recommended to only use smart chargers. Good NiMH only smart chargers include:
– Panasonic BQ-CC65 – advanced 4 bay smart charger
– Panasonic BQ-CC63 – 8 bay smart charger
– Panasonic BQ-CC55 – best value 4 bay smart charger
Unless you are only ever intending on using NiMH batteries, I would recommend looking at multi-chemistry chargers (see Li-ion section) that can charge both NiMH and li-ion batteries.
For rechargeable C, D, and 9V batteries and chargers options are limited. Varta and Rayovac sell rechargeable C, D, and 9V batteries and a (sadly) “dumb” charger.
Some very small “keyring” flashlights and glow sticks may use lithium button/coin batteries. Be extremely careful with button batteries around children, as there have been many cases of permanent injury and death in children who have swallowed them.
Lithium CR123A (3V) batteries are non-rechargeable, and were quite popular in the earlier years of LED flashlights. They have a good shelf life and can handle large temperature ranges. Unfortunately, they have been known to explode if they reverse charge (2 in series with different voltages). They have largely been superseded by rechargeable Li-ion batteries, and thus I don’t recommend using CR123A batteries.
Li-Ion Overview and Safety
Most of this buying guide will focus on Li-ion batteries, which are pretty much essential of you want to use high brightness flashlights. The vast majority of Li-ion batteries used in flashlights have a max voltage of 4.2V, and a nominal voltage of 3.6/3.7V. Whilst newer IMR and INR Li-ion batteries are more chemically stable than older ICR types, use of Li-ion batteries still requires knowledge of the safety risks required to safely use these batteries.
Key Li-ion safety aspects so as to avoid damaging the battery are as follows:
- Do not charge above 4.2V. Chargers in the recommendation list should terminate charge at 4.2V.
- Do not discharge below 2.5V. Look for flashlights with low voltage protection, or mechanically lock out the flashlight if possible (usually by unscrewing the tail cap). If you do discharge below 2.5V, re-activating the battery should be using low current, with frequent checking that the battery does not get too hot! If in doubt, dispose of the battery at a recycling point.
- Use a charger with voltage readout.
- For lights that use more than one Li-ion battery in series or parallel, you must use matching batteries and they must always be at the same voltage before use (check using a charger with voltage readout). If voltages are not the same, you risk reverse charging, and possible explosion.
- Always insert batteries with the correct polarity. Some flashlights have reverse polarity detection or prevention.
- Do not short circuit the battery.
- Store spare batteries in plastic cases. No one likes battery explosions in their trousers!
- Do not use damaged li-ion batteries, this includes damaged wrappers.
- Do not charge or discharge at currents higher than the battery’s rating.
- Batteries with added protection circuits will help prevent over charge, over discharge, or over-current. However, protection circuits are an additional point of failure.
- Avoid older and more volatile ICR chemistry Li-ion batteries where possible.
- Always periodically check on the batteries during a charge – I don’t advise charging at night or if you are out of the house.
- Charge, and store batteries and flashlights in less flammable locations – plastic battery containers are useful.
- Remove batteries from flashlights if they will be out of use for a while – beware of parasitic drain!
- Keep batteries out of reach of children, and people with no common sense.
- Li-ion batteries will degrade slower if stored closer to 50% capacity (around 3.6-3.7V)
If you were very unfortunate, and a Li-ion battery starts to heat up rapidly (thermal runaway), quickly leave it in as safe a place as possible and keep your distance. The pressure build up during a battery vent will cause an explosion from both ends of the flashlight tube (and side if there is a side button). If there is a source if ignition, there may be flames and resulting fire. Avoid breathing in the fumes, and call the fire brigade immediately.
Li-ion batteries have names that denote the approximate size of that battery in mm. The first two numbers are width, and the second two are length. Examples include 14500, 16340, 18350, the commonly used 18650, 26650, 20700, and 21700. Unfortunately, that is where the standardisation ends, especially when you add protection circuits onto the ends of some batteries. 18650s can vary between 18mm x 65mm in unprotected batteries, up to 18.8mm x 71mm in the largest protected batteries. Not all 18650 batteries will fit in a flashlight as they may be too short, too long, or too wide. Some flashlights require button tops, some don’t. Thus it is advised to read reviews, or follow manufacturer recommendations of battery sizes that will fit.
All protected batteries have the protection circuit added by companies that are not the original manufacturer, and most have button tops. Protected Li-ion batteries are often included with flashlights, and if you purchase from a reputable flashlight manufacturer, they should be of high quality. However if they are not included, you will need to purchase your own. Most recommended 18650 batteries are in the 2600 to 3600mAh capacity range.
Best Protected 18650 for Maximum capacity:
– Blazar 3500mAh 10A (Australia)
– KeepPower 3500mAh 10A Protected (Worldwide)
– Orbtronic 3500mAh 10A (USA)
– Nitecore 3500mAh 10A (Worldwide)
Note: There are no genuine 18650 batteries with a capacity more than 3600mAh!
Best Protected 18650 for Maximum current:
– Klarus 18GT-IMR31 3100mAh 12A
– AceBeam 3100mAh 20A
– KeepPower 3000mAh Protected 15A
Best Protected 18650 for Cold Temperatures (-40C)
– Klarus 18GT-LT29 2900mAh 8A
– Nitecore NL1829LTHP 2900mAh 8A
More advanced flashlight users may want to use unprotected batteries, and some flashlights such as the BLF/Lumintop FW1A only accept unprotected batteries. Usually unprotected batteries have a flat top, but some are also available with added button tops for lights that require them such as the BLF/Thorfire/Sofirn Q8.
Best Unprotected 18650 for Maximum Capacity
– Panasonic/Sanyo NCR18650GA 3500mAh 10A – most recommended – this is what I use in most lights!
– Samsung INR18650-35E 3500mAh 10A
– LG MJ1 3500mAh 10A
Best Unprotected 18650 for Maximum Current
– Sony US18650VTC6 3000mAh 30A – most recommended
– Sony US18650VTC5A 2600mAh 35A – highest current, though overkill for flashlights!
– Samsung INR18650-30Q 3000mAh 15A
– LG INR18650-HG2 3000mAh 20A
There are an increasing number of 21700 lights suitable for light painting such as the Lumintop FW21.
Best Unprotected 21700:
– Samsung 50E 5000mAh 10A – best for capacity
– Samsung 40T 4000mAh 35A – best for high current
If in doubt, go with the flashlight manufacturer’s recommended battery!
Some flashlights, or even some 18650 batteries, have internal charging mechanisms, using USB (micro, or USB-C) or magnetic chargers. These are very popular with the consumer market, and are generally of high quality in reputable flashlight brands. Be aware that some magnetic charging connections need to be kept away from conductive materials such as steel wool so as to avoid a short circuit!
I would highly recommend purchasing dedicated multi chemistry chargers (NiMH and Li-ion) that allow you to keep an eye on voltage, or have battery analysing functionality such as internal resistance, and capacity testing. I no longer recommend any basic Li-ion chargers without voltage display, or budget analysing chargers with known QC issues.
Best NiMH/Li-ion Chargers (voltage display):
– Nitecore UMS2
– Nitecore UMS4 – Nitecore’s most advanced charger
– Nitecore D2
– Nitecore D4
– GyrFalcon All-44
– GyrFalcon All-88 – best 8 slot charger
– XTAR VC2
– XTAR VC2S – best 2 slot charger with USB power supply
– XTAR VC4
– XTAR X2 – excellent value and quality 2 slot charger
– XTAR X4 – excellent value and quality 4 slot charger
Best Analysing NiMH/Li-ion Chargers (voltage display, internal resistance, and capacity testing):
– Vapcell S4+ – increasingly popular with flashlight enthusiasts
– XTAR VC4S – best value 4 slot analysing charger, with USB power supply
– XTAR DRAGON VP4 Plus – most recommended but fairly expensive – this is what I use!
– SkyRC MC3000 – most advanced analysing charger, but for experts/enthusiasts only
Li-ion – What To Avoid
Unfortunately, there are a lot of very bad and dangerous Li-ion batteries available (including from Amazon, eBay, and other online electronics retailers), with highly over-exaggerated current and capacity ratings. Any 18650 battery with a capacity over 3600mAh is fake or misleading! Brands to avoid include Ultrafire, GTL, GIF, SkyWolfeye, Meco, and Elfeland. There have been many reports on flashlight forums of Ultrafire batteries exploding – ouch!
Where to buy Li-ion batteries
Due to safety reasons, Li-ion shipping is quite problematic. Many Chinese electronics retailers have stopped shipping to some countries. Thus it is often easier to purchase from as close to home as possible. Bricks and mortar flashlight and vape stores are good places to start, but can be expensive. Online retailers recommended on flashlight forums include: