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The Battery Page
This page is a reference section for battery information relevant to e-cigarette use - and especially for APVs (e-cigarettes with large, user-replaceable generic rechargeable batteries, usually with one or more features or functions not available in a mini e-cigarette).
Part 1 - this post
Part 2 - next post
To edit / add to this page, see at foot.
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General advice
DO NOT USE UNPROTECTED RECHARGEABLE LI-ION batteries IN AN APV
Use a safer-chemistry battery such as Li-Mn or hybrid
Note 1: we no longer recommend protected Li-ion (ICR) as an automatic choice.
- IMR (Li-Mn) or hybrids are now (2014-03-21) a far better choice for all removable-cell devices of any kind: mechmod APVs, electrically switched APVs, and electronically-regulated APVs (VV and VW).
- ICR (protected Li-ion) is now for specific, well-chosen applications and generally means a low current draw of <3A is required.
- They require a special charger, or the switch on a dual-voltage charger to be correctly positioned - which means mistakes will be made.
- They are a commonly counterfeited battery, and could be re-covered reject unprotected Li-ion cells instead of Li-FePo4 - it may be impossible to verify the supply chain or what the battery really is. Because these cells are normally used in series, there is a significant elevation of risk with counterfeit cells.
- Although they are probably the most stable of all lithium cells, their heyday was back when 2-cell mechmods were popular for 6 volt vaping, and that time has gone. They have few modern applications in vaping.
ONLY USE RECHARGEABLE BATTERIES - DO NOT USE ORDINARY NON-RECHARGEABLE CELLS
(often called 'lithium camera batteries')
Mechmods (mechanical APVs) with RBAs (rebuildable atties) may not work with a protected Li-ion cell because the current demand is too high. A safer-chemistry cell is a better choice.
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Rest batteries after charging
One commonly-reported factor in almost all the incidents we hear of where batteries failed violently while in use is that they were taken directly off the charger and then used immediately, at which point they failed.
Because of this, we think it may be a good idea to rest batteries after charging them. This advice will not be found in the usual 'reference bibles' on batteries, but we see more and different reports than others. Therefore we now advise:
Do not use batteries directly after charging them. Use a battery or batteries you previously charged, and that have rested for several hours. This is especially important if using a stacked pair for higher voltage, as statistically the risk is far higher.
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Our advice is that the best and the safer choice of battery for APVs is the AW IMR Li-Mn rechargeable.
It is a safer-chemistry battery that needs no protection, and has a high-discharge rating meaning that it is safer to use with high-current devices such as atomizers. Here is a good post on battery safety that lists many safer-chemistry batteries and their specifications:
(9) Battery Basics for Mods: IMR or Protected ICR? | E-Cigarette Forum
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Many think the best option is the largest AW Li-Mn battery that can be fitted (this is partly due to the fact that the supply chain can be verified if due diligence is used). Other safer-chemistry cells where the supply chain is verifiable are an equally-good choice; counterfeit batteries are a problem because the label is false and therefore the battery could be anything.
But please note that no lithium rechargeable battery can be regarded as 'safe' - that simply is not possible. When we refer to 'safer', we mean the reduction of the possibility of blowing up in the face of a user who has just taken the battery off charge and is applying a heavy current draw to the device. An atomizer is regarded as a heavy current draw for this size of battery. No other definition of relative 'safety' is inferred.
Lithium batteries of all types are all capable of catching fire if mistreated. This might be by overcharging due to a faulty charger; being placed in a confined space and shorted out (such as in an APV, in a pocket, with the master switch not set to off and either the on button pressed continually or an internal fault in the unit); or similar mistreatment.
Rechargeable lithium batteries are not safe in an absolute sense and should never be regarded as being so.
While eGo-type batteries are ideally recharged in a Li-Po charging sack on a fire-proof surface such as cement, stone, tile or brick, the best solution for removable batteries is probably in a cake tin (aka biscuit tin) with vent holes drilled in it (as the charger will not overheat).
NEVER leave cells unattended while charging.
APVs need basic safety features such as a locking actuator switch (good) or a master on/off switch separate from the main actuator switch (best), and some form of gas vents.
Two-cell non-electronic devices should have substantial gas vents (electronic devices are safer as they provide fusing that cannot be bypassed).
If you choose to ignore these points then you must accept the consequences.
Lithium rechargeables are not absolutely safe, and neither is an APV with them in. No statement anywhere on ECF may be taken to mean that any particular make of battery is 'safe'. Safe is not a term that can be used for lithium ion cells, which have well-known risks. Some are much safer than others, though, and IMR or hybrid types are safer than ICR cells of any kind.
Battery fires
The most common type of battery fire occurs with mid-size (eGo type) units on charge. The next most common, although less frequent, are battery pocket/purse fires where a loose cell was being carried, and the battery shorted out on coins and keys. Don't carry batteries loose - get a battery box (eBay) or an ecig case.
A note on IMR, ICR and hybrid
IMR means Lithium Manganese. In fact it is a misnomer because although we say "i m r" it should be "L m r", as it refers to 'lithium manganese rechargeable'. The font used caused a confusion between L and I, but it's too late to change now. Lithium manganese cells are a safer chemistry type that need no protection circuit on the battery itself.
ICR means Lithium Cobalt. The same confusion has occurred with L and I. Lithium cobalt cells are the regular Li-ion type that need a protection circuit added on to the negative pole of the battery in order to achieve acceptable safety. They are then called a 'protected battery'. The basic chemistry of these cells means that they are not as safe as IMR cells. They cannot be used in high current draw applications either, because although the bare cell can cope with high loads, the tiny electronics in the protection circuit cannot, and there is a maximum practical limit of 2 or 3 amps.
ICR cells are obsolete now, and there is no reason at all to choose them. There is one possible exception: where a low current draw is needed over an extended period of time, they can sometimes be the best choice. In other words, if you vape at 1.5 amps and want a cell that will last slightly longer between charges, then this is about the only profile that benefits from an ICR cell. In practice they are almost always a poor choice.
Hybrid cells are a combination-technology variant where (generally) Li-Mn is combined with another type. They are a safer-chemistry type that can deliver high current.
Battery counterfeiting
This is a growing problem and all APV users need to be aware of it.
This is what happens: the counterfeiters buy reject Li-ion batteries in bulk, strip the covers off, and re-cover them with labels that change them to look like popular brands. In this way they can take a cell bought for 10 cents, re-work it, and sell it as for example an AW battery with a retail price of $10. The profits are very high and this practice is growing. It means that you never really know what battery you have unless you buy from somewhere with a verified supply chain. For example, all AW batteries offered for sale on Alibaba are counterfeits, and possibly dangerous.
Buy the best batteries
Please don't try to save money on batteries, it is the worst possible area to make economies. It's like trying to buy the cheapest possible parachute, with no idea where it comes from or who made it, and pretending there is no increase in risk. Why would you do that?
Only use safer-chemistry rechargeables such as Li-Mn or Hybrid in an APV.
Protected rechargeable Li-ion batteries, or high-quality Li-FePo4 can also be used for specific applications.
Suitable batteries of any type generally have a C rating of greater than 4C or 2 amps or 2,000mA, and this should now be regarded as the absolute minimum [see Note 1].
For single-cell VV or VW electronic devices, the C rating needs to be at least 5 amps (more is better).
For RBAs the C rating must be very much higher, and 10 amps is regarded as the minimum for safe operation unless the current draw is kept low by keeping the coil resistance high.
Primary and secondary cells
A rechargeable is also called a secondary cell. An ordinary, non-rechargeable battery is called a primary cell.
Lithium rechargeables (of any kind) are normally called lithium ion cells. Only use rechargeable batteries. Never use standard batteries (primary cells) in any kind of APV. Standard batteries = stock cells / primary cells / ordinary batteries. This is because they can be mixed with rechargeables by mistake, put in a charger, then used in an APV - resulting in an explosion on first operation of the device (and this has happened). Charging a primary cell often results in fire or explosion, and the main risk is that this can occur on first load demand.
This can also occur with an unprotected Li-ion rechargeable of course - but the explosion with a standard battery is especially violent as there are no gas vents built in to the battery. In one explosion of an APV involving standard batteries that had been recharged by mistake then used in a 6 volt device, it was reported that a broken jaw and lost teeth were caused.
Explosions may be due to thermal runaway when a faulty cell is overcharged then put in an overcurrent situation (which atomizer use frequently is, since most small cells cannot safely provide enough power for an atomizer, which might draw 2.5 amps). Protected batteries have a small electronic package built in that trips out in case of various fail modes. However Li-Mn (and some Li-FePo4) batteries can handle heavier loads safely.
The more batteries and the higher the volts then the higher the risk. Incidents have occurred with a single unprotected battery, but when they are placed in series the risk is higher. Statistically, 2-cell 6 volt+ mechmod users are more likely to experience an incident, and are the only group experiencing explosive incidents*. Battery fires occur in even the most expensive VV devices - basically it is impossible to completely prevent them with lithium cells (phones and laptops have thousands of such fires).
* Update Q3 2015
We have now seen some explosive incidents in 2015 with 1-cell 18650 mechmods and RBAs. This appears to be due to super-high current draws exceeding 50 amps or possibly even in the 100-amp range, when using ultra-low resistance coils for cloud chasing. Perhaps the batteries were counterfeits although at this stage it is impossible to say. There is some basic advice that can be given here although it is very likely that those who most need it will not take any heed of it:
- If using coils of 0.2 ohms or below, more safety precautions are needed (for example you must be very sure your battery is not a counterfeit or a cheap product)
- Metal tube mechmods pulling super high amps need substantial gas vents in case of a fault that leads to a battery failure
- A 26650 cell is intrinsically safer for this type of ultra high load duty as it is bigger and can take more abuse before failing (we have no reports of a 26650 cell failing violently)
The highest risk of all is the use of two batteries in a metal tube APV that appears to be sealed. This is partly because you do not know what those batteries are, as counterfeiting is so widespread now. IT IS WHY METAL TUBEMODS MUST HAVE OBVIOUS SAFETY FEATURES SUCH AS VERY LARGE GAS VENTS with the possible exception of fully-electronic models as they have no serious incident history. Assume that your two batteries are cheap reject (faulty) unprotected Li-ion cells - BECAUSE THEY COULD VERY WELL BE, no matter what it says on the label.
Li-Mn or hybrid cells are intrinsically safer and in any case will deliver far more current for modern applications than protected Li-ion cells.
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[Note 1]
There are now some forms of safer technology batteries such as Li-Mn, Hybrid and some but not all Li-FePo4 - see below - these don't need protection circuits built in. It may be wise to build a protection circuit into the APV though, as they can discharge a very high current in a short-circuit* condition.
* A 'short-circuit' = a 'dead short' = a 'short' = a direct connection between the positive and negative terminal through the device's casing or circuitry
ALL APVs NEED A LOCKING SWITCH, OR (BETTER) A MASTER ON/OFF SWITCH SEPARATE FROM THE ACTUATOR SWITCH.
METAL TUBEMODS NEED LARGE GAS VENT HOLES.
DON'T BUY AN APV WITHOUT THESE FEATURES AS YOU MAY BE INCREASING YOUR RISK SUBSTANTIALLY.
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Rechargeable batteries
We now advise that Li-Mn or Hybrid rechargeables are used in APVs, in preference to protected rechargeable Li-ions. We suggest the best option, in order, is:
1. AW IMR Li-Mn rechargeables.
2. Panasonic or similar hybrid cells. (Sony spinel cells are new on the market at the date of edit [2013-09-01] and it is likely they will also prove acceptable, they are an Li-Mn type). You must ensure that these cells are sourced from an authorised distributor, as they will become extensively counterfeited.
3. AW Li-FePo4 rechargeables [Li-FePo4's mostly NEED A SPECIAL CHARGER]. Note that these batteries are mostly 3 volt nominal so the system voltage will be lower than normal. They are the best choice for stacking as long as they are not counterfeits.
4. Good quality (such as AW or Pila) protected Li-ion rechargeables.
5. Branded protected Li-ions come next - such as *fire Li-ion rechargeables (for *, insert Trust / Sure / Ultra-).
6. The least-preferable option is a generic protected Li-ion.
7. Unprotected rechargeable Li-ion cells should not be used.
8. Standard cells (non-rechargeable) MUST NOT be used.
Li-FePo4 cells can be used provided that they are top-quality, ideally they should have a rating of 4C or higher. They are only suitable for specialised applications now.
If using Li-ions then protected rechargeables are advised, as standard 3.7 volt Li-ion lithium rechargeable batteries can explode under certain circumstances which protection circuits generally prevent (over-charging, short-circuit, over-discharge, over-voltage). Thermal runaway (leading to violent de-gassing or explosion) sometimes occurs with these batteries, as they generally have a 1C rating, that is to say, the discharge rate is 1x the capacity - which is not enough reserve power to efficiently power an atomizer, which demands more amps than a small Li-ion battery can effectively deliver (about 4 or 5 times more). This means they are being overstressed. An over-charge incident followed by a high-current demand may result in thermal runaway - in other words the battery may explode on first use after recharging.
This is not a frequent occurrence - but it does happen. Note that the likelihood of this particular fail mode occurring can be minimized by using the largest batteries possible, since they are not then overstressed. More incidents occur with small batteries like the RCR123 than large batteries, probably for this reason.
Protection circuits trip out and usually stop these events. The protection circuit is built-in to the battery - the copper surface you can see at the negative end of the battery is the bottom face of the circuit board the electronics are on. Protected batteries are therefore physically longer than their unprotected cousins, as the circuit board has to be added to the lower end of the cell.
However, there are some batteries such as Li-Mn, Hybrid and Li-FePo4 that do not require on-battery protection as their chemistry is safer [see #1 above]. These batteries can still present risks in some circumstances (if short-circuited for example). As they are not available in protected form, protection should be incorporated into the device. These 'safer chemistry' types are not known to explode, but will go into meltdown with flames if abused.
Li-Mn or hybrid cells are intrinsically safer and in any case will deliver far more current for modern applications than protected Li-ion cells.
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Rechargeable battery types
Li-ion rechargeables
These batteries are in fact Li-CoO2 (aka Li-Co), lithium cobalt dioxide. The nominal voltage quoted is 3.6 or 3.7 volts, which is the same thing - there is no general agreement on whether to call lithium cells 3.6v or 3.7v cells. The 3.7 volt rechargeables are the basic unit used in APVs.
It is safer to use the protected versions since Li-ion batteries are vulnerable to thermal runaway and violent out-gassing or even explosion in some fail modes, which are probably due to a chain of three faults such as faulty batteries, overcharging, and overdriving. The hot gas expelled is a mix of hydrogen, methane and ethylene, which will not ignite in anaerobic state (without air/oxygen) but burns fiercely as soon as it contacts and mixes with the oxygen in air. The main risk is with using two batteries in series ('stacking') in an APV with no safety features. Since an explosion is likely to be right in front of the user's face on first use of newly-charged batteries when energising the atomizer for the first time, some nasty injuries can AND HAVE been received. A small number of people have been severely injured, and others have received minor injuries. Don't use unprotected Li-ion cells, and make sure your APV has safety features.
One incident that occurred to a flashlight (torch) user resulted in lithium poisoning lasting several days, from chemical inclusion in the wounds resulting from an explosion. Flashlight users have been using lithium cells (and in sealed-unit high-power applications) for much longer than ecig users, and have the best data on lithium cell incidents since they have experienced hundreds or perhaps thousands of them. See the Candlepower forum, for example.
THESE BATTERIES ARE POTENTIALLY DANGEROUS - WE ONLY ADVISE USE OF THE SAFER-CHEMISTRY TYPE
A Li-ion battery has no 'charge memory', so it can be charged at any point of the discharge cycle with no ill-effects. It does NOT need a long first charge, or a 'conditioning' first-use full-discharge then a full charge. These are memory effects seen in other battery types such as Ni-Cad and DO NOT APPLY to Li-ion batteries. It's true that a cell may not work at full capacity for the first charge or two but this is not a memory effect.
These batteries are a nominal 3.6 or 3.7 volts (which is the same thing). They are charged fully at 4.2 volts and best recharged at around 3.4 volts. They must not be discharged below 3 volts or they will be damaged. They can be recharged at any time during the cycle as they have no 'memory' like the old Ni-Cads - and in fact it is advisable to recharge them before they reach full discharge, as this extends their service life. In theory they take 300 recharges but that is under ideal conditions - 150 is more likely to be achieved in practice. Don't fully discharge them - they will live longer.
Li-ions do not have a good C-rating, for use in high-discharge current applications such as powering an e-cig atomizer. Also, like many products, batteries are often over-rated and the *actual* real-life rating is nearer 0.5C, not the 1C often given by the manufacturer. For example the typical real-life discharge rating of a RCR123 Li-ion rechargeable is about 500mA, half an amp, which as you can see is too low to power any kind of atomizer properly as they draw 1 amp and up. This is one reason batteries die - they are worked far too hard. These batteries are in effect not up to the job as they are too small. Physical size is important in a battery.
Advantages of Li-ion batteries:
- Very high charge density compared to Ni-Cad or Ni-Mh 1.2 volt cells ('main street' rechargeables).
- Low self-discharge rate.
- No memory effects.
- Reasonable service life, about 150 - 200 recharges.
- Cheapest from of lithium cell.
Disadvantages:
- Poor high-current discharge performance.
- Applications that require high current (like e-cigs) will shorten the life of the battery.
- Unprotected batteries might be used by mistake, these are dangerous in high-current use mode, they can AND DO explode especially if used in series and then overdriven.
- The protection electronics can fail due to being zapped by static, or a faulty charger - so the battery is rendered unsafe and there is no indication of this. It usually fails safe, i.e. dead - but this cannot be guaranteed.
- These cells would be a poor choice for use in a mechmod with an RBA (a mechanical APV using a rebuildable atomiser system, where the coil resistance might be low either by design or accident) because the current draw would be too high for sufficient safety margin.
All batteries of the type we are referring to - Li-ion, Li-Mn, Li-FePo4 - are actually Li-ion cells, but we just use the term 'Li-ion' to refer to the Li-Co type.
Li-Mn or hybrid cells are intrinsically safer and in any case will deliver far more current for modern applications than protected Li-ion cells.
IMR Li-Mn rechargeables
Manufacturers include AW and BDL. AW are reported as higher quality. These batteries are unlikely to explode in use and there are no reports of this occurring (but they can melt down with flames if abused by for example short-circuiting or APV switch lock-on). They are recommended in place of Li-ions and do not need protection. These batteries are of high quality and are therefore expensive - but you get what you pay for.
Notes:
- No memory effect.
Cautions:
- They have a high current discharge potential and therefore it may be wise to have a protection circuit in the main device. The discharge rating is often 8C, meaning it is likely that a lot of amps would be available if the battery were to be short-circuited (= a dead short or shorted-out).
- They will be overcharged by old-technology chargers and may burst.
- Overcharging (>4.25 volts) will shorten the service life, which is 500 charges under ideal conditions.
- Discharging below 3 volts will shorten the service life.
- If you run a Li-Mn down below the minimum discharge voltage, the cell can be damaged. As there is no 'trip out' as with a protected Li-ion, this is a concern.
You can extend the service life of these cells by not recharging above 4.16 volts or discharging below 3.4 volts.
Hybrid rechargeables
These modern hybrid-technology cells combine Li-Mn with other battery technologies. They are a safer-chemistry type. We don't currently have enough history with them to fully detail their pros and cons.
Advantages of hybrid cells:
- They are a safer-chemistry type and need no protection
- They can deliver high currents and have high C ratings
- Quality is good because they come from the most respected names in battery technology
- Some cells (check C rating as there is a wide variation) are a good choice for the toughest ecig applications (e.g. sub-ohm RBAs)
Disadvantages of hybrids:
- They are not a cheap battery
- Because there are several different types, we don't know if all factors apply to all types
- They will soon be counterfeited, like AW's cells, so make sure to buy from an authorised dealer
- If you buy from Alibaba for example, to get a good deal, then don't be surprised if you get a counterfeit
Li-FePo4 rechargeables
These lithium ferrous phosphate batteries have a safer chemistry. Li-FePo4 is a newer technology and more expensive than Li-ion. This is a safe technology and they don't need any protection. AW batteries make these, and they are a very good choice as they are capable of taking the high load of an e-cig. They come in the same form-factor as the Li-ions used in ecig APVs and are an excellent substitute, preferable in all ways except for the cost - however, note the 2 cautions below.
Notes:
- Very long service life of 1,000 charges, under ideal conditions.
- No memory effect.
- Fast recharge.
Cautions:
- Do not connect in parallel.
- 2 cells max in series.
- Discharge rate is commonly 5C to 8C, sometimes 10C, so they will certainly power atomizers effectively - but short-circuits need to be guarded against. The 26650 cell for example can put out 70 amps in a dead short.
- Nominal voltage (type 1 eg RCR123 format) = 3.0 - 3.3v, min. discharge v = 2.8v, max. charge voltage = 3.6v; nominal voltage (type 2 eg AW 14500 Li-FePo4)= 3.6v.
Special cautions:
- Needs a special charger - different for the two types.
- Some Li-FePo4 cells have a low discharge rate (C rating) of less than 1C - so it would be advisable to check the discharge rating before purchase.
AW brand Li-FePo4 cells are reported as being the best.
We have one report of a Li-FePo4 failure in an APV, but it might have been due to one of these two reasons:
1. Tenergy Li-FePo4 cells are reported as being widely counterfeited. Because the batteries YOU are using could be counterfeits, it is VITAL that your APV has clearly visible safety features such as large gas vents. DOES IT?
2. CAUTION: most Li-FePo4 batteries have a working voltage much lower than the Li-ion equivalent - 3.2 volts - and they CANNOT be used with Li-ion chargers.
AW do make a 3.6 volt Li-FePo4 battery (their 14500 model) but this is not the norm for Li-FePo4. There is a very good chance that some users of Li-FePo4's will overcharge them, leading to failure, since the MAXIMUM charge voltage is 3.6 volts but the common Li-ion chargers put out 4.2 volts. Because of this, AW's Li-Mn rechargeables are thought to be the best option for APVs.
NEVER place 3v batteries in a 3.7v (normal) charger. Li-FePo4's, with very few exceptions, are 3v batteries. These RCR123 format cells can be placed in series for a nominal 6 volts. Special precautions need to be taken with stacked batteries.
Ni-Mh rechargeables
These are the stock rechargeables found on main street. They come in the usual AA and AAA formats, with a nominal voltage of 1.5 volts although the real voltage is just 1.2 volts per cell - so 3 or 4 cells in series are needed for e-cigarette use. They are a safe technology and do not explode with mild abuse, and can be safely placed in series ('stacked'). No protection circuitry is needed. An APV can be built successfully using these standard rechargeables although it is worth pointing out that the C rating of most cells will be too low, leading in theory to shortening of service life.
There are some minor disadvantages (shorter life etc) but on the whole they can be used successfully. Each cell delivers 1.2 volts, so some adjustment of the battery numbers / arrangements has to be made. For example 3 in series will provide 3.6 volts (good for normal e-cig use, with an on-load voltage probably around 3.3v), and 4 in series gives 4.8 volts (about 4.5 volts on load). These standard rechargeables are a good choice for APVs that are specifically built for the form factor and voltage requirements. It is likely that there will be noticeable voltage drop unless C-size cells are used; few 14500-size cells (= AA size) have enough C rating to run an atomizer.
Notes:
- Available everywhere.
- The multi-cell battery holders found in electronics stores can easily be used as a boxmod case.
- Safe technology, no explosions even when stacked.
Cautions:
- In theory, a shorter service life. This does not seem to have been found to be the case in APV tests though, as many Li-ions don't last long in practice.
- Lower voltage so more cells are needed - at least 3 cells in series, and 4 is better.
Li-Poly rechargeables
These lithium polymer battery packs are normally square/flat. Their use is not common in APVs. They are typically used in RC planes and cars. However more APVs are coming on the market with integral Li-Poly battery packs that cannot be changed by the consumer.
We don't recommend the larger Li-Poly packs as they seem to be more delicate than other types and can apparently catch fire after impact damage such as being dropped, or while recharging after being dropped (see the battery fire videos linked below, which all involved Li-Poly packs). We are hoping that the smaller packs do not suffer from this issue.
Tenergy Li-FePo4 batteries
This is an interesting subject. Here are some of the factors:
- Tenergy Li-FePo4 3 volt cells have a manufacturer's C rating of about 0.75.
- If the manufacturer rates a cell at about 0.5 amps safe discharge, ECF cannot then tell people it is suitable for use at 2.5 amps. You can probably see why.
- Independent tests seem to show, however, that these batteries are good quality and will perform at 4C with no problem. This would make them ideal for use as a stacked pair for 6v vaping.
- However, and most importantly, it looks as if these could be the most counterfeited battery out there. In other words you may think you have a pair of Tenergy Li-FePo4 batteries but in fact you have a pair of junk reject re-covered unprotected Li-ion cells: the most dangerous situation possible.
So, what is the answer? If you know for sure you have genuine Tenergy 3v Li-FePo4 batteries, it seems as if they could be very suitable (although we cannot officially say that for obvious reasons when the manufacturer says they cannot take more than a half-amp load). But you need to be very careful indeed because there is a chance the batteries might be fakes. That could leave you in a dangerous situation, if used stacked in a metal tubemod.
SEE PART 2, in next post
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Members with specific technical knowledge are invited to help improve this page.
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Updated 2014-03-21 - page split into two parts; ICR recommendation demoted
Updated 2014-03-20 - added IMR, ICR explanation; hybrid cell list reference
Updated 2013-09-01 - added ref to Panasonic hybrid cells and Sony Spinel cells
Updated 2012-04-24 - changed refs to APV from mods
Updated 2012-04-15 - added advice to rest batteries after charging
Updated 2012-03-10 - added latest info on Tenergy batteries
Updated 2012-03-08
Updated 2012-01-21
Updated 2011-05-23
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