- Status
I pretty much use Eneloop rechargeables for household stuff except wall clocks. When I do buy Alkaline AA or AAA it's usually Energizers or Rayovac. The Duracells are more expensive and don't really perform any better. The Eneloops are more economical in remotes, BP monitors, bathroom scales, cameras, flashlights, toys etc. For some reason, they don't work that well for me in clocks tho.
No, not for vaping.
Honestly, I wanted some quality batteries for a headlamp, a couple of flashlights and an LED clock that I recently purchased.I always prefer rechargeables. Regular single-use batteries always seem to end up with that white corrosion.
Trouble with 'em is they don't work well in applications that actually need ~1.5V per cell. They also tend to have a relatively high self-discharge, which makes them unsuitable for really low-draw, long-term applications like a wall clock.
I saved this huge wall of text from a review of a charger that comes with eneloop batteries. There's some good info in it for someone like me who didn't know much.
This package (Panasonic K-KJ17KHCA4A Eneloop Pro Individual Cell Battery Charger with 4 AA Ni-MH Rechargeable Batteries) contains the BQ-CC17 charger and four eneloop Pro batteries. People often ask me whether it is worthwhile to pay extra for this 'Pro' package over a similar 'regular' package. So here is a breakdown on the Pros and Cons of going Pro:
- The rated capacity of eneloop Pro AA cell is 2550mAh, or 27.5% higher than that of regular eneloop cell (2000mAh). My measured average capacities using the La Crosse BC1000 Battery Charger are around 2560mAh and 2080mAh, respectively.
- The cycle life rating of Pro is only 500 cycles, verses 2100 cycles for regular eneloop. More about this later.
- The advertised charge-retention rate of Pro cell ("85% after 1 year") is not as good as that of regular eneloop cell ("90% after 1 year, 70% after 10 years"). Those rating are consistent with my own long-term test results. Of course in real life this hardly matters.
- The Pro AA cell is slightly thicker than regular eneloop cell, so it might not fit in appliances with extremely tight battery compartments.
The chargers included in the Pro and Regular packages are identical except for color. So this is not a factor. See my review on BQ-CC17 for details of this charger.
[Capacity Matters?]
Obviously higher-capacity for batteries is better, because it gives you longer runtime for each recharge. This is especially true in the old days of NiCd batteries, since you are supposed to drain them completely before recharge (to avoid 'Memory Effects'). With pre-charged NiMH batteries and smart charger such as the BQ-CC17, you can choose to top-off your batteries anytime. So having higher capacity is less critical.
Just for example, let's say you are using rechargeable batteries in your external photo flash unit. Assuming a set of regular eneloop cells (2000mAh) can give you 1000 flashes, then by changing to Pro cells (2550mAh) you can expect 1275 flashes. But unless you actually need to shoot over 1000 pictures in one session, the extra capacity does not offer you any advantage.
[Cycle Life Matters?]
This rating refers to the number of deep-discharge cycles a battery goes through, before its capacity drops to 50% of original value. That means:
- Regular eneloop starts from 2000mAh and drops to 1000mAh after ~2100 cycles
- eneloop PRO starts from 2550mAh and drops to 1275mAh after ~500 cycles
Note that those ratings are based on tightly controlled test conditions. In real life your numbers will likely be less.
Assuming linear degradation of capacity, we can estimate that after 250 cycles:
- Regular eneloop --> 2000mAh - 1000mAh*(250/2100) = 1881mAh
- eneloop PRO --> 2550mAh - 1275mAh*(250/500) = 1912mAh
That means shortly after 250 cycles, the regular eneloop cell will actually out-perform the Pro!
[Bottom Line]
If you have mission-critical applications that demand the extra capacity offered by eneloop Pro batteries, definitely get this Pro package. Otherwise for similar cost, you can get the regular package plus another 4 regular eneloop (or the equivalent AmazonBasics Pre-Charged) batteries. So now you have 8x 2000mAh eneloop batteries instead of 4x 2550mAh eneloop Pro batteries. This approach offers you almost 60% more in total battery energy. Most importantly, you now have a set of spare batteries to swap in whenever the first set runs out, so you'll never be out of action while batteries are being recharged.
###############
December 22, 2015
Style: AASize: 4-PackConfiguration: Batteries only
[Note: The following is an updated version for my original “Sanyo eneloop FAQ”, first published in May 2012]
I have been using eneloop low-self-discharge NiMH batteries since beginning of 2007, and I'm completely satisfied with them. One thing I noticed is that newcomers to the rechargeable battery arena often have similar questions/confusions about eneloop. So here is my list of eneloop Frequently Asked Questions. This list is work in progress.
[Q1] Why are there so many eneloop batteries with different capacity ratings and cycle-life numbers?
[A] There are actually three families of eneloop batteries:
- Standard version: The original Sanyo eneloop (circa 2006) was rated for capacity of 2000mAh typical for AA (800mAh for AAA) and 1000-cycle lifespan. Subsequent generations advertise longer lifespan (1500/1800/2100-cycles) at the same capacity. The charge retention rates have steadily extended from "85% after 1 year" to "90% after 1 year; 70% after 5 years"
(Refer to my uploaded photo on how to identify different generations of eneloop cells)
- High-Capacity version: The original Sanyo XX (circa 2010) was rated for 2500mAh but only 500 cycles. The charge-retention rate is slightly poorer at "75% after 1 year". Newer Panasonic eneloop PRO bumped the capacity to 2550mAh and charge-retention rate to "85% after 1 year".
- LITE version: Those have half the capacity of standard eneloop but twice the cycle life. They are not marketed in the US.
[Q2] Do I get better performance from the latest generation Panasonic eneloop cells verses earlier generation Sanyo eneloop cells?
[A] On paper, newer generation offers longer cycle life and lower self-discharge rate. In practice, however, you’ll see no difference since they all have the same capacity. The difference in charge retention rate and cycle life may become noticeable after ~10 year, if at all.
[Q3] Is there any physical difference between PRO and standard version of eneloop cells?
[A] The PRO cells are slightly thicker, with diameter of ~14.4mm (verses ~14.1mm). So they may not fit if your appliance’s battery compartment is too tight-fitting.
[Q4] What is the difference between 'Pre-Charged', 'Hybrid', 'Stay-Charged', 'Active Charged', 'Ready to Use' and 'Ready to Go'?
[A] Those are all marketing terms for Low-Self-Discharge (...) NiMH batteries. Sanyo first used the term 'Pre-Charged' for Sanyo eneloop back in 2006. The latest Panasonic eneloop says “Ready to use” on each cell.
[Q5] I see a lot of other brands of rechargeable batteries advertised as Pre-Charged. Are they just as good Panasonic eneloop?
[A] In general, NO. Sanyo/Panasonic eneloop is still the best in terms of charge retention rate and cycle life. Many lesser-known brand also claim to have low self discharge rate and high cycle life just like eneloop. But based on my testing, none actually delivers.
[Q6] What about the AmazonBasics Pre-Charged Rechargeable Batteries?
[A] To clarify, there are three different versions of AmazonBasic rechargeable NiMH batteries:
- The original AmazonBasics AA NiMH Pre-Charged Rechargeable Batteries came in black wrappers. They are made in China and have the capacity rating of 2000mAh. They are NOT as good as Sanyo eneloop batteries.
- The second version of AmazonBasics Pre-Charged Rechargeable Batteries came in white wrappers. They are made in Japan and also have the capacity rating of 2000mAh. They appear to be rebranded 2nd-gen eneloop.
- The third version is also black but called AmazonBasics High-Capacity Pre-Charged Rechargeable Batteries. They appear to be rebranded eneloop PRO. They are rated 2400mAh, but actual capacity is around 2550mAh.
[Q7] How do the Duracell Ion Core pre-charged Batteries compare to eneloop or AmazonBasics cells?
[A] The Duracell 'ion core' AA cells appear to be rebranded eneloop PRO AA cells, while the Duracell AAA cells are most likely rebranded 2nd-gen eneloop AAA.
[Q8] My Panasonic eneloop AA batteries say '1900mAh' on them. Are they counterfeits?
[A] All standard eneloop AA cells (from original to 4th gen) are rated "Typical 2000mAh, Minimum 1900mAh". The confusing part is that 2nd-to 4th-gen eneloop AA cell have "min.1900 mAh" printed on it, even though the actual measured capacity is typically over 2000mAh.
For AAA cells: Standard eneloop are rated "Typ 800mAh, Min 750mAh".
[Q9] How do I find out the manufacture date of my new eneloop cells?
[A] Each eneloop cell has a date code embossed on it. Shine a strong flashlight from the side and slowly rotate the cell to find it. Date codes are in the form of YY-MM. For example, if it says '12-08' that means Aug 2012.
[Q10] Date codes on my new eneloop cells indicate they are made in 2012. Should I return then for newer batteries?
[A] Relax! Unlike ordinary NiMH cells, Sanyo eneloop are still perfectly good even after 10 years in storage. Once you recharge them, they will return to 100% capacity again.
[Q11] I just received some new eneloop batteries. Do I need to recharge them before use?
[A] You can use them right out of the package. However, standard eneloop cells are only charge up to ~75% when they left factory (High-capacity version usually just ~50%), So you can use a Smart charger to 'top-off' their charges. Do NOT do this with a Dumb charger because it will badly over-charge them.
[Q12] I thought I have to drain my batteries completely before recharging them?
[A] This is only necessary if you are using a timer-based dumb charger. With a smart charger, you can top-off your batteries anytime.
[Q13] Can I use other brands of chargers to recharge Sanyo eneloop batteries?
[A] Sanyo eneloop batteries can be recharged using any good-quality Smart charger designed for NiMH cells. But for longer battery lifespan, avoid ultra-fast (15- or 30-minute) chargers and Dumb (overnight) slow chargers
[Q14] What is the difference between 'Smart' and 'Dumb' chargers?
[A] A Smart charger monitors the voltage profile of each cell individually during charging, and stops when a charge-termination signal (negative delta-Voltage) is detected. This is the only way to avoid over-charging. A Dumb charge relies on safety timer to stop charging, or has no termination mechanism at all. This usually results in over-charging which is bad for battery lifespan.
[Q15] How good is the Sanyo MQN06 charger bundled with most older eneloop packages?
[A] The MQN06 is semi-smart but has two issues: it charges in pairs (monitors the combined voltage of two cells), and the charging current is only 300mA. That means it take about 7 hour to recharge a pair of eneloop AA cells. A better choice is the Panasonic BQ-CC17 which charges each cell individually (but still at the same 300mA current)
[Note: Charge time (hour) = Capacity (mAh) / Current (mA) ]
[Q16] What is the best charging speed for eneloop cells?
[A] Choose a charger that gives you charge time between 2-5 hours. That means charging current of 400-1000mA for AA, 200-500mA for AAA..
[Q17] Isn't it true the best charging speed for NiMH and ...-NiMH battery is the slowest?
[A] That’s only true when using a dumb charger which blindly charges for 12-15 hours, so the current has to be below 0.1C (200mA for a 2000mAh cell) to avoid over-heating. For a smart charger, the current needs to be at least 0.2C to ensure proper termination. If the charging current is too low, the negative delta-V detection may not work reliably. (The BQ-CC17 is an exception since it uses pulsed current)
[Q18] I always keep a set of ordinary NiMH batteries in the charger to keep them freshly charged. So why do I need low-self-discharge batteries?
[A] You don't need to do that with ... cells. Just charge up a spare set ahead of time and keep them in your drawer. Swap them in whenever needed, just as how you use disposable cells.
[Q19] Why should I buy those 2000mAh eneloop instead of regular NiMH batteries that are rated 2700mAh or higher?
[A] All rechargeable NiMH AA cells rated 2700mAh or higher are susceptible to rapid-self-discharge problem. Beware of off-brand batteries that claim '3000mAh' or higher. Most of them can't even deliver 2000mAh.
[Q20] Can I use eneloop in places with extremely hot or cold weather?
[A] As a rule of thumb, every 10 degree C rise in temperature causes the battery's self-discharge rate to double. So although your eneloop cells can still function correctly, their shelf life will be reduced at high ambient temperature.
For cold weather it is not a problem, since eneloop cells are rated down to -20 degree C.
[Q21] Should I store unused eneloop batteries in the refrigerator to extend their shelf life?
[A] For ordinary NiMH cells, storing them in lower temperature greatly reduces their self-discharge rate so you can get longer shelf life. For eneloop cells it is not worth the trouble, because they can be stored for years at room temperature.
[Q22] Can I use eneloop batteries in cordless phones?
[A] Yes - as long as your phones (such as Panasonic DECT 6.0 cordless phones) are using individual AAA cells, instead of battery packs with special connectors.
[Q23] Do rechargeable batteries only go bad after they meet the number of charging cycles, or their lifespan is limited by time also?
[A] Capacity of a NiMH cell gradually deteriorates with number of discharge cycles. The 'lifespan' claimed by manufacturer is the number of deep-discharge cycles before capacity drops to 50%. This is done under tightly controlled test conditions, so in real life your result may vary.
[Q24] When rechargeable batteries go bad, do they also spill chemicals (like alkaline cells) or just won't hold a charge?
[A] Good-quality NiMH cells do not spill electrolyte as they gradually deteriorate. The only chance this can happen is when they are (a) severely over-charged at a high current, (b) severely over-discharged, or (c) exposed to extreme heat.
[Q25] My baby swing calls for 4 D sized batteries. Do eneloop D spacers work well?
[A] You can use those in a pinch, but expect to replace/recharge your AA cells a lot more frequently than before. This is because the energy stored in an alkaline D cell is about 7-10 times greater than that in eneloop AA cell. See my following review for other options: Panasonic BQ-BS1E4SA Eneloop D Size Spaces
[Q26] My La Crosse BC-700 Battery Charger reports some eneloop batteries as 'null'. Are they defective?
[A] If a battery is over-discharged and its voltage drops below 0.5V, the La Crosse charger cannot detect it and so the display says 'null'. Charge your 'null' battery in a dumb charger for a few minutes, then the La Crosse charger will recognize it.
[Q27] Is the La Crosse BC-700 better than the Panasonic BQ-CC17?
[A] Each has its advantages. The BQ-CC17 is inexpensive, simple to use, and works great for daily charging.
The BC-700 is an Advanced charger. It allows you to determine the true capacity (mAh) of all your batteries, and to revive those under-performing cells. Then you can group cells with similar capacities together for best result. See my "BC-700 FAQ" for details:
BC-700/900/1000 FAQ
[Q28] Panasonic introduced a new charger, the BQ-CC55. Is it worth paying extra over the old BQ-CC17?
[A] Yes, for two main reasons:
(1) Shorter charge time: since its average charging current is 1.4A for 1-2 AA cells, 0.7A for 3-4 cells.
(2) Color-changing LEDs to show the status of each cell: Red=empty, Yellow=half-full, Green=full.
See my review on it for details: Big improvement over previous generations of eneloop battery chargers
This package (Panasonic K-KJ17KHCA4A Eneloop Pro Individual Cell Battery Charger with 4 AA Ni-MH Rechargeable Batteries) contains the BQ-CC17 charger and four eneloop Pro batteries. People often ask me whether it is worthwhile to pay extra for this 'Pro' package over a similar 'regular' package. So here is a breakdown on the Pros and Cons of going Pro:
- The rated capacity of eneloop Pro AA cell is 2550mAh, or 27.5% higher than that of regular eneloop cell (2000mAh). My measured average capacities using the La Crosse BC1000 Battery Charger are around 2560mAh and 2080mAh, respectively.
- The cycle life rating of Pro is only 500 cycles, verses 2100 cycles for regular eneloop. More about this later.
- The advertised charge-retention rate of Pro cell ("85% after 1 year") is not as good as that of regular eneloop cell ("90% after 1 year, 70% after 10 years"). Those rating are consistent with my own long-term test results. Of course in real life this hardly matters.
- The Pro AA cell is slightly thicker than regular eneloop cell, so it might not fit in appliances with extremely tight battery compartments.
The chargers included in the Pro and Regular packages are identical except for color. So this is not a factor. See my review on BQ-CC17 for details of this charger.
[Capacity Matters?]
Obviously higher-capacity for batteries is better, because it gives you longer runtime for each recharge. This is especially true in the old days of NiCd batteries, since you are supposed to drain them completely before recharge (to avoid 'Memory Effects'). With pre-charged NiMH batteries and smart charger such as the BQ-CC17, you can choose to top-off your batteries anytime. So having higher capacity is less critical.
Just for example, let's say you are using rechargeable batteries in your external photo flash unit. Assuming a set of regular eneloop cells (2000mAh) can give you 1000 flashes, then by changing to Pro cells (2550mAh) you can expect 1275 flashes. But unless you actually need to shoot over 1000 pictures in one session, the extra capacity does not offer you any advantage.
[Cycle Life Matters?]
This rating refers to the number of deep-discharge cycles a battery goes through, before its capacity drops to 50% of original value. That means:
- Regular eneloop starts from 2000mAh and drops to 1000mAh after ~2100 cycles
- eneloop PRO starts from 2550mAh and drops to 1275mAh after ~500 cycles
Note that those ratings are based on tightly controlled test conditions. In real life your numbers will likely be less.
Assuming linear degradation of capacity, we can estimate that after 250 cycles:
- Regular eneloop --> 2000mAh - 1000mAh*(250/2100) = 1881mAh
- eneloop PRO --> 2550mAh - 1275mAh*(250/500) = 1912mAh
That means shortly after 250 cycles, the regular eneloop cell will actually out-perform the Pro!
[Bottom Line]
If you have mission-critical applications that demand the extra capacity offered by eneloop Pro batteries, definitely get this Pro package. Otherwise for similar cost, you can get the regular package plus another 4 regular eneloop (or the equivalent AmazonBasics Pre-Charged) batteries. So now you have 8x 2000mAh eneloop batteries instead of 4x 2550mAh eneloop Pro batteries. This approach offers you almost 60% more in total battery energy. Most importantly, you now have a set of spare batteries to swap in whenever the first set runs out, so you'll never be out of action while batteries are being recharged.
###############
December 22, 2015
Style: AASize: 4-PackConfiguration: Batteries only
[Note: The following is an updated version for my original “Sanyo eneloop FAQ”, first published in May 2012]
I have been using eneloop low-self-discharge NiMH batteries since beginning of 2007, and I'm completely satisfied with them. One thing I noticed is that newcomers to the rechargeable battery arena often have similar questions/confusions about eneloop. So here is my list of eneloop Frequently Asked Questions. This list is work in progress.
[Q1] Why are there so many eneloop batteries with different capacity ratings and cycle-life numbers?
[A] There are actually three families of eneloop batteries:
- Standard version: The original Sanyo eneloop (circa 2006) was rated for capacity of 2000mAh typical for AA (800mAh for AAA) and 1000-cycle lifespan. Subsequent generations advertise longer lifespan (1500/1800/2100-cycles) at the same capacity. The charge retention rates have steadily extended from "85% after 1 year" to "90% after 1 year; 70% after 5 years"
(Refer to my uploaded photo on how to identify different generations of eneloop cells)
- High-Capacity version: The original Sanyo XX (circa 2010) was rated for 2500mAh but only 500 cycles. The charge-retention rate is slightly poorer at "75% after 1 year". Newer Panasonic eneloop PRO bumped the capacity to 2550mAh and charge-retention rate to "85% after 1 year".
- LITE version: Those have half the capacity of standard eneloop but twice the cycle life. They are not marketed in the US.
[Q2] Do I get better performance from the latest generation Panasonic eneloop cells verses earlier generation Sanyo eneloop cells?
[A] On paper, newer generation offers longer cycle life and lower self-discharge rate. In practice, however, you’ll see no difference since they all have the same capacity. The difference in charge retention rate and cycle life may become noticeable after ~10 year, if at all.
[Q3] Is there any physical difference between PRO and standard version of eneloop cells?
[A] The PRO cells are slightly thicker, with diameter of ~14.4mm (verses ~14.1mm). So they may not fit if your appliance’s battery compartment is too tight-fitting.
[Q4] What is the difference between 'Pre-Charged', 'Hybrid', 'Stay-Charged', 'Active Charged', 'Ready to Use' and 'Ready to Go'?
[A] Those are all marketing terms for Low-Self-Discharge (...) NiMH batteries. Sanyo first used the term 'Pre-Charged' for Sanyo eneloop back in 2006. The latest Panasonic eneloop says “Ready to use” on each cell.
[Q5] I see a lot of other brands of rechargeable batteries advertised as Pre-Charged. Are they just as good Panasonic eneloop?
[A] In general, NO. Sanyo/Panasonic eneloop is still the best in terms of charge retention rate and cycle life. Many lesser-known brand also claim to have low self discharge rate and high cycle life just like eneloop. But based on my testing, none actually delivers.
[Q6] What about the AmazonBasics Pre-Charged Rechargeable Batteries?
[A] To clarify, there are three different versions of AmazonBasic rechargeable NiMH batteries:
- The original AmazonBasics AA NiMH Pre-Charged Rechargeable Batteries came in black wrappers. They are made in China and have the capacity rating of 2000mAh. They are NOT as good as Sanyo eneloop batteries.
- The second version of AmazonBasics Pre-Charged Rechargeable Batteries came in white wrappers. They are made in Japan and also have the capacity rating of 2000mAh. They appear to be rebranded 2nd-gen eneloop.
- The third version is also black but called AmazonBasics High-Capacity Pre-Charged Rechargeable Batteries. They appear to be rebranded eneloop PRO. They are rated 2400mAh, but actual capacity is around 2550mAh.
[Q7] How do the Duracell Ion Core pre-charged Batteries compare to eneloop or AmazonBasics cells?
[A] The Duracell 'ion core' AA cells appear to be rebranded eneloop PRO AA cells, while the Duracell AAA cells are most likely rebranded 2nd-gen eneloop AAA.
[Q8] My Panasonic eneloop AA batteries say '1900mAh' on them. Are they counterfeits?
[A] All standard eneloop AA cells (from original to 4th gen) are rated "Typical 2000mAh, Minimum 1900mAh". The confusing part is that 2nd-to 4th-gen eneloop AA cell have "min.1900 mAh" printed on it, even though the actual measured capacity is typically over 2000mAh.
For AAA cells: Standard eneloop are rated "Typ 800mAh, Min 750mAh".
[Q9] How do I find out the manufacture date of my new eneloop cells?
[A] Each eneloop cell has a date code embossed on it. Shine a strong flashlight from the side and slowly rotate the cell to find it. Date codes are in the form of YY-MM. For example, if it says '12-08' that means Aug 2012.
[Q10] Date codes on my new eneloop cells indicate they are made in 2012. Should I return then for newer batteries?
[A] Relax! Unlike ordinary NiMH cells, Sanyo eneloop are still perfectly good even after 10 years in storage. Once you recharge them, they will return to 100% capacity again.
[Q11] I just received some new eneloop batteries. Do I need to recharge them before use?
[A] You can use them right out of the package. However, standard eneloop cells are only charge up to ~75% when they left factory (High-capacity version usually just ~50%), So you can use a Smart charger to 'top-off' their charges. Do NOT do this with a Dumb charger because it will badly over-charge them.
[Q12] I thought I have to drain my batteries completely before recharging them?
[A] This is only necessary if you are using a timer-based dumb charger. With a smart charger, you can top-off your batteries anytime.
[Q13] Can I use other brands of chargers to recharge Sanyo eneloop batteries?
[A] Sanyo eneloop batteries can be recharged using any good-quality Smart charger designed for NiMH cells. But for longer battery lifespan, avoid ultra-fast (15- or 30-minute) chargers and Dumb (overnight) slow chargers
[Q14] What is the difference between 'Smart' and 'Dumb' chargers?
[A] A Smart charger monitors the voltage profile of each cell individually during charging, and stops when a charge-termination signal (negative delta-Voltage) is detected. This is the only way to avoid over-charging. A Dumb charge relies on safety timer to stop charging, or has no termination mechanism at all. This usually results in over-charging which is bad for battery lifespan.
[Q15] How good is the Sanyo MQN06 charger bundled with most older eneloop packages?
[A] The MQN06 is semi-smart but has two issues: it charges in pairs (monitors the combined voltage of two cells), and the charging current is only 300mA. That means it take about 7 hour to recharge a pair of eneloop AA cells. A better choice is the Panasonic BQ-CC17 which charges each cell individually (but still at the same 300mA current)
[Note: Charge time (hour) = Capacity (mAh) / Current (mA) ]
[Q16] What is the best charging speed for eneloop cells?
[A] Choose a charger that gives you charge time between 2-5 hours. That means charging current of 400-1000mA for AA, 200-500mA for AAA..
[Q17] Isn't it true the best charging speed for NiMH and ...-NiMH battery is the slowest?
[A] That’s only true when using a dumb charger which blindly charges for 12-15 hours, so the current has to be below 0.1C (200mA for a 2000mAh cell) to avoid over-heating. For a smart charger, the current needs to be at least 0.2C to ensure proper termination. If the charging current is too low, the negative delta-V detection may not work reliably. (The BQ-CC17 is an exception since it uses pulsed current)
[Q18] I always keep a set of ordinary NiMH batteries in the charger to keep them freshly charged. So why do I need low-self-discharge batteries?
[A] You don't need to do that with ... cells. Just charge up a spare set ahead of time and keep them in your drawer. Swap them in whenever needed, just as how you use disposable cells.
[Q19] Why should I buy those 2000mAh eneloop instead of regular NiMH batteries that are rated 2700mAh or higher?
[A] All rechargeable NiMH AA cells rated 2700mAh or higher are susceptible to rapid-self-discharge problem. Beware of off-brand batteries that claim '3000mAh' or higher. Most of them can't even deliver 2000mAh.
[Q20] Can I use eneloop in places with extremely hot or cold weather?
[A] As a rule of thumb, every 10 degree C rise in temperature causes the battery's self-discharge rate to double. So although your eneloop cells can still function correctly, their shelf life will be reduced at high ambient temperature.
For cold weather it is not a problem, since eneloop cells are rated down to -20 degree C.
[Q21] Should I store unused eneloop batteries in the refrigerator to extend their shelf life?
[A] For ordinary NiMH cells, storing them in lower temperature greatly reduces their self-discharge rate so you can get longer shelf life. For eneloop cells it is not worth the trouble, because they can be stored for years at room temperature.
[Q22] Can I use eneloop batteries in cordless phones?
[A] Yes - as long as your phones (such as Panasonic DECT 6.0 cordless phones) are using individual AAA cells, instead of battery packs with special connectors.
[Q23] Do rechargeable batteries only go bad after they meet the number of charging cycles, or their lifespan is limited by time also?
[A] Capacity of a NiMH cell gradually deteriorates with number of discharge cycles. The 'lifespan' claimed by manufacturer is the number of deep-discharge cycles before capacity drops to 50%. This is done under tightly controlled test conditions, so in real life your result may vary.
[Q24] When rechargeable batteries go bad, do they also spill chemicals (like alkaline cells) or just won't hold a charge?
[A] Good-quality NiMH cells do not spill electrolyte as they gradually deteriorate. The only chance this can happen is when they are (a) severely over-charged at a high current, (b) severely over-discharged, or (c) exposed to extreme heat.
[Q25] My baby swing calls for 4 D sized batteries. Do eneloop D spacers work well?
[A] You can use those in a pinch, but expect to replace/recharge your AA cells a lot more frequently than before. This is because the energy stored in an alkaline D cell is about 7-10 times greater than that in eneloop AA cell. See my following review for other options: Panasonic BQ-BS1E4SA Eneloop D Size Spaces
[Q26] My La Crosse BC-700 Battery Charger reports some eneloop batteries as 'null'. Are they defective?
[A] If a battery is over-discharged and its voltage drops below 0.5V, the La Crosse charger cannot detect it and so the display says 'null'. Charge your 'null' battery in a dumb charger for a few minutes, then the La Crosse charger will recognize it.
[Q27] Is the La Crosse BC-700 better than the Panasonic BQ-CC17?
[A] Each has its advantages. The BQ-CC17 is inexpensive, simple to use, and works great for daily charging.
The BC-700 is an Advanced charger. It allows you to determine the true capacity (mAh) of all your batteries, and to revive those under-performing cells. Then you can group cells with similar capacities together for best result. See my "BC-700 FAQ" for details:
BC-700/900/1000 FAQ
[Q28] Panasonic introduced a new charger, the BQ-CC55. Is it worth paying extra over the old BQ-CC17?
[A] Yes, for two main reasons:
(1) Shorter charge time: since its average charging current is 1.4A for 1-2 AA cells, 0.7A for 3-4 cells.
(2) Color-changing LEDs to show the status of each cell: Red=empty, Yellow=half-full, Green=full.
See my review on it for details: Big improvement over previous generations of eneloop battery chargers
Eneloop are by far the most trusted, tried and true option. Ikea and Amazon equivalents are possibly rebranded Eneloop as well. Fujitsu makes solid rechargeables as well.
For most applications the white label Eneloop are best; good performance and long lifespan.
However, Eneloop Pro is a consideration as well - about 20% more capacity, but shorter overall lifespan. Worth noting they are just a tad bit thicker, so fitment might be an issue in tight spaces but I've never had this issue.
In terms of flashlights...I use white Eneloop mostly in lights I frequently use. I have a few sets of Pro when the extra runtime is needed.
I have a lightweight headlamp I use for running that takes a single AAA, so the Pros help squeeze some extra time if needed.
For most applications the white label Eneloop are best; good performance and long lifespan.
However, Eneloop Pro is a consideration as well - about 20% more capacity, but shorter overall lifespan. Worth noting they are just a tad bit thicker, so fitment might be an issue in tight spaces but I've never had this issue.
In terms of flashlights...I use white Eneloop mostly in lights I frequently use. I have a few sets of Pro when the extra runtime is needed.
I have a lightweight headlamp I use for running that takes a single AAA, so the Pros help squeeze some extra time if needed.
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Not sure why you posted this here... but I will say a few things. Standard alkaline batteries duracell are the best for something you don't use (but want to have ready... even months later) Otherwise other batteries mentioned may be better. Something that has high draw the NimH are amazing (and expensive) We just replaced alkaline with those for a battery light setup with a bunch of LEDs (christmas decoration) and they were so much brighter! Recharge just makes more sense overall, and some of the small (AA... don't remember the brand) you can buy a bunch with adapters (because they have high mAH ratings) that can replace C and D cells (one size fits all mentality) Some low draw applications do not benefit from higher power batteries at all.
I actually thought you were posting this because you wanted to make a "home-made" mech mod with a bunch of AA batteries in series/parallel LOL.
I actually thought you were posting this because you wanted to make a "home-made" mech mod with a bunch of AA batteries in series/parallel LOL.
I use flashlights with T6 LEDs and for those I use 18650 cells, even though most of those lights also work with a 3 cell AAA adapter. I have lots of 18650's and 20700's around from vaping, so it all works together.
I use alkaline rechargeables, NiMH cells. Those I use in some of my guitar accessories such as tuners and remote belt pack wireless transmitters for my guitars. I use 9v for my pedal accessories. There are 2400 NiMh cells out these days. The field is widening to the point where rechargeables are equal to alkaline throwaways. Most of the AAA's I have for guitar accessories are only 800mah. I need to look at some new technology in batteries!
I use alkaline rechargeables, NiMH cells. Those I use in some of my guitar accessories such as tuners and remote belt pack wireless transmitters for my guitars. I use 9v for my pedal accessories. There are 2400 NiMh cells out these days. The field is widening to the point where rechargeables are equal to alkaline throwaways. Most of the AAA's I have for guitar accessories are only 800mah. I need to look at some new technology in batteries!
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Sorry, none. But it looks like you got some great suggestions!
for my led headlamps, diving torch and small torch
i bought ones that use 18650s
while all at the moment are using batteries salvaged from old lap tops ( they generally dont have enough max discharge current for vape gear )
i can in an emergency use spares from my vape gear .. although i haven't had to as they last many hours already
my mosquito zapper racket and outdoor ir led floods also use 18650s
yehh guess who is a fan boy for reusing 18650 rechargeable s
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AAA is quite limited unfortunately. I think the highest capacity for rechargeable is probably going to be about 1000 mAh. Eneloop Pro AAA probably are going to be the most stable and reliable and those are about 950 mAh, I believe.
Energizer Lithium AAA have the highest capacity with 1250 mAh, but obviously those are not rechargeable.
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