RX100 Generic 1600 mAh NP-BX1 Battery Review

[LSHorwitz1]

Ron,



I have 4 Sony chargers here for my 4 Sony cameras, as well as numerous other chargers for camcorders, laptops, and other lithium ion batteries.



All of my lithium ion battery chargers have at least 3 terminals to charge their batteries. Although it is possible to safely charge lithium ion batteries using only two terminals at a slow rate so as to avoid overheating, the standard practice is to use a heat sensing thermistor on a third terminal as shown in the schematic of Figure 6 which I posted earlier.



Those who read the news and see the experiences of Sony, Apple, Tesla, Boeing, GM, and many others who use lithium batteries know that the risks of overheating and fire are very real and very dangerous.



I have attached photos of the 4 Sony camera chargers I have here which essentially handle most of the Sony batteries and cameras currently being marketed.




4 chargers above for WX/RX, HX, NEX7, alpha batteries


















Larry

 

[Ron AKA]

Interesting. Have you looked close enough to see where the pins contact the battery? The Sony charger for the W570 has three contacts, but one of them is a duplicate. Two adjacent contacts on the charger contact the single negative terminal on the battery. So effectively it only has two contacts. No pin on the charger contacts the C terminal on the battery. Perhaps that is just because it is a budget camera and Sony also cut corners, or also perhaps because it is only a 250 mA charger that they are not concerned about heat.

The adapter for the in camera RX100 is rated at 1500 mA, which is three times the nominal USB current capability. Perhaps they are more concerned about heating during charging.

 

[LSHorwitz1]

Ron,



The three Sony chargers for the alpha, NEX, and HX batteries each provide 3 contacts connecting to three battery terminals (+ C - ) whereas the fourth Sony charger for the X batteries such as in my WX and the RX cameras has 4 contacts connecting to 4 battery terminals (C - T +).

None of these is a 2 terminal only connection.



Larry

 

[1AvidHiker]

I have also seen Sony-branded chargers with three terminals, but with one very clearly being a duplicate (you can usually see it's the same contact, just with two contact points). These have always been external chargers supplied as accessories with the camera (i.e., the cheapest charger Sony could find). My W200 came with a wall charger that I can see is only making 2 connections with the battery, but it is VERY slow compared with the "fast" charger that Sony sells separately at a premium (which appears to have additional safety features).

As someone has already pointed out, and I believe this is the key here, these cheap chargers are not charging anywhere near the maximum safe rate, which can be in the 1-2C range for higher-end electronics. The maximum safe rate will depend on the exact Li-ion chemistry and safety circuitry (C refers to the relation of charge current to battery capacity, some good reading here: http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries) Looking at the OEM battery for the RX100, I see they list a maximum charge current of 1.89A - this is equivalent to 1.5C, which is a fairly fast charge for a consumer device (but not unusual in a premium camera). Although charging the battery in-camera with the supplied 1.5A USB adapter might not quite hit this rate, I suspect it should be pretty close.

So, compared with the cheap wall charger supplied with these $20 aftermarket battery kits (750mA output I think), this is quit a bit faster. I have the Wasabi 2 battery kit with wall charger and haven't found anything wrong with it. The only things I have noted WRT aftermarket Li-ion batteries are:

1. There should be no concern about aftermarket batteries supplying the correct voltage or otherwise meeting the camera's power requirements because (a) voltage regulation is done in-camera and (b) all common Li-ion chemistries have essentially the same voltage profile (4.2V fully charged, ~3.2V empty) and current delivery capabilities.

2. These aftermarket batteries either show full charge or low charge (meaning you have a minute or two left) on the RX100's 4-segment battery status display, so be aware that they can die suddenly on you with no warning. Apparently they (or at least the ones I have) do not allow the camera to keep track of the remaining charge, which is typically just a matter of measuring the resting voltage of the cell (this tracks very closely with remaining charge). Older Sony batteries used a more advanced system (InfoLithium) which kept track of the cell performance (which changes over the cell's life) to allow for a more exact runtime display, but it appears they have switched to a simpler method (which I suspect is resting voltage, but there could be more to it). Interestingly, the camera does still warn you when these batteries are nearly exhausted, which would suggest that the camera may still be monitoring charge status. So, it could be they just disable the charge status display when the camera detects a non-OEM battery (I'll take that over the dreaded "for use with compatible battery only" message some Sony cameras give). Anyway, at least they give you a 2 minute warning.

3. The battery capacity listed on these aftermarket products is almost always inflated and they almost always offer less runtime compared with the OEM battery (I seem to get a little less runtime out of these wasabi batteries, but not much less, maybe 10-20%).

4. To remove any chance of damage to your camera, always use the supplied aftermarket charger EXCLUSIVELY to charge an aftermarket battery (this charger should also be perfectly safe to use on the OEM battery). Since you know nothing about how different these batteries are, you cannot assume it is safe to charge the aftermarket battery in-camera (especially if it is doing something to trick the camera into accepting it). In-camera charging with the RX100 is definitely much faster than the aftermarket charger, so this may not be safe.

In fact, the only problems I have occasionally seen reported with these cheap batteries are failures when they are being charged in-camera - the battery can suddenly expand and you will not be able to remove it without taking the camera apart. FWIW, this was much more commonly reported 4-5 years ago (don't think I have even seen any recent reports). So, it seems these aftermarket brands may have improved the reliability of their products. Anyway, I wouldn't assume there is zero risk involved, but the risk should be pretty minimal.

 

[Ron AKA]

I have the Wasabi 2 battery kit with wall charger and haven't found anything wrong with it.

Have you checked the T terminal on the Wasabi battery to see if it really has a thermistor, or if it is just faking it with a simple resistor?

 

[L Copps]

The protective design protects primarily against overheat when charging, NOT during in-camera use / discharge, although it could be also used in this manner as well.

Of course the external battery charger eliminates any chance of this happening. Also, OEM batteries are not immune from problems themselves. I have had some very bad batteries made by Sony when I lived in Japan. At any rate, its much safer to charge batteries in a third party external charger than in the camera.

Of course. All manufacturers of electronics use a large percentage of parts made by other vendors. Some select and use better and more expensive parts and others select and use cheaper parts. Look carefully at your eBay batteries and chargers. No way are they the same as Sony's despite the very well known practice of counterfieting. Sony even puts holographic labelling on their batteries to prevent consumers from being ripped off by knock-offs.

But if we buy OEMs we are definitely being ripped off by Sony. I do not buy any batteries from ebay, they tend to be of very questionable quality. I buy mine from Amazon and I have been pleased with their quality. I am not worried about safety. I do not leave batteries charging in the camera and the Physics of the chemistry will not allow the battery to surge past what the voltage regulator will tollerate.

 

[lester11]

Nice analysis, I'd forgotten about the dreaded swelling in the body problem... The RX100 user manual tells me to expect the in-camera battery charge to take around 155 minutes; given the 1240 mAh nominal capacity, that is a pretty close match to the 500 mA draw from a USB connection. So that's around 0.4C? Manual also says the max charge current for the battery is 1.89 A, so that is a max. of around 1.5C.

--
Lester

 

[Ron AKA]

1AvidHiker wrote:

In fact, the only problems I have occasionally seen reported with these cheap batteries are failures when they are being charged in-camera - the battery can suddenly expand and you will not be able to remove it without taking the camera apart.

I think that is much less of a risk now. Boeing bought up all those batteries and put them in their Dreamliner!

Seriously I am not all that worried about the generics. I first used one when my Garmin GPS battery failed. The Garmin battery and whole GPS would get so hot that you could hardly hold it, and died about 20 seconds after you unplugged it from the car. Garmin wanted over $100 to replace it, and you have to send it in to them to do it. You can buy a new GPS for that much.

I bought a generic on eBay for less than $5 and installed it myself. No, it is not real easy, but it can be done if you have the right tools or can innovate. This generic has much longer life than the OEM Garmin, and does not get hot when charging.

 

[LSHorwitz1]

L Copps wrote:

The protective design protects primarily against overheat when charging, NOT during in-camera use / discharge, although it could be also used in this manner as well.

Of course the external battery charger eliminates any chance of this happening. Also, OEM batteries are not immune from problems themselves. I have had some very bad batteries made by Sony when I lived in Japan. At any rate, its much safer to charge batteries in a third party external charger than in the camera.

The external battery charger does NOT eliminate any chance of this happening. Without a temperature tracking thermistor to sense actual battery temperature, an external charger can overcharge and also overheat the battery. And yes, OEM batteries can also have their problems..........The chances of getting a bad battery when they are sold as generic, cheap eBay items or as knock-offs increases the chances of getting a bad battery substantially.

Of course. All manufacturers of electronics use a large percentage of parts made by other vendors. Some select and use better and more expensive parts and others select and use cheaper parts. Look carefully at your eBay batteries and chargers. No way are they the same as Sony's despite the very well known practice of counterfieting. Sony even puts holographic labelling on their batteries to prevent consumers from being ripped off by knock-offs.

But if we buy OEMs we are definitely being ripped off by Sony. I do not buy any batteries from ebay, they tend to be of very questionable quality. I buy mine from Amazon and I have been pleased with their quality. I am not worried about safety. I do not leave batteries charging in the camera and the Physics of the chemistry will not allow the battery to surge past what the voltage regulator will tollerate.

Not sure what you mean by "the Physics of the chemistry" but I assure you that voltage regulation on the charger is only a partial explanation of how battery and charger safety are actually considered by engineers who do the designs. The lack of temperature sensing means that the battery can and will overheat under some conditions, and then the only remaining safeguard is the integrity of the vents and the strength of the case, both of which need to contain the overpressure or allow it to dissipate in a controlled and vented manner. The really cheapo designs use a slow, low current charging technique to avoid this issue, and never raise the internal temperature as much. This is done by extending the charging time a great deal, something many people do not like but others do not care about. Note that these are not voltage regulated as you stated, but rather are current limited.

Larry

 

[L Copps]

The external battery charger does NOT eliminate any chance of this happening. Without a temperature tracking thermistor to sense actual battery temperature, an external charger can overcharge and also overheat the battery. And yes, OEM batteries can also have their problems..........The chances of getting a bad battery when they are sold as generic, cheap eBay items or as knock-offs increases the chances of getting a bad battery substantially.

Can't see how you can ruin a camera with an external battery charger unless the charger burns the house down. And this can happen with a Sony battery. But a charger cannot gain a UL certification without a heat activated fuse. I once bought a Sony made battery from Sony's flagship store in Ginza. It got hot when charged and only worked for a few cycles before it would no longer accept any charge. I have used Wasabi batteries for my GoPro H3 which come with a charger. Worked better than GoPro's batteries. They also stand behind their product. I'm sure their Sony NP-BX1 battery set works great too and at a great price.

Not sure what you mean by "the Physics of the chemistry" but I assure you that voltage regulation on the charger is only a partial explanation of how battery and charger safety are actually considered by engineers who do the designs. The lack of temperature sensing means that the battery can and will overheat under some conditions, and then the only remaining safeguard is the integrity of the vents and the strength of the case, both of which need to contain the overpressure or allow it to dissipate in a controlled and vented manner. The really cheapo designs use a slow, low current charging technique to avoid this issue, and never raise the internal temperature as much. This is done by extending the charging time a great deal, something many people do not like but others do not care about. Note that these are not voltage regulated as you stated, but rather are current limited.

The Physics of the battery chemistry will not let it hold a charge that the camera's voltage regulator cannot handle. I also doubt the camera can discharge the battery with enough amperage to cause the battery to damage the camera. The only heat risk will come from charging in the camera. If you charge the batteries outside the camera, there is no way they can cause damage from heat. As far as leakage, I am not convinced Sony batteries would fare any better than Wasabi batteries. Good reason not to store the camera for long periods of time with the battery.

 

[L Copps]

Battery systems that produce hundreds of amps for the Boeing Dreamliner are far more complicated than trickle charging a single NP-BX1 cell. Even so, I always charge my RX100 batteries in an external charger. Eliminates the risk. Thermistor or no Thermistor. If it burns up on the charger, no big deal.

 

[Ron AKA]

Did you know that the early Toyota Prius Hybrids ran on consumer C cells from Panasonic. They put a whole bunch in series as the hybrids use up to 245 volts DC, but not much current. Toyota bought the technology from Panasonic and I believe they now make a custom battery for the Prius and Camry hybrid, but it is still small like a C cell.

One might be surprised what they put in the Dreamliner...

 

[LSHorwitz1]

L Copps wrote:

The external battery charger does NOT eliminate any chance of this happening. Without a temperature tracking thermistor to sense actual battery temperature, an external charger can overcharge and also overheat the battery. And yes, OEM batteries can also have their problems..........The chances of getting a bad battery when they are sold as generic, cheap eBay items or as knock-offs increases the chances of getting a bad battery substantially.

Can't see how you can ruin a camera with an external battery charger unless the charger burns the house down. And this can happen with a Sony battery. But a charger cannot gain a UL certification without a heat activated fuse. I once bought a Sony made battery from Sony's flagship store in Ginza. It got hot when charged and only worked for a few cycles before it would no longer accept any charge. I have used Wasabi batteries for my GoPro H3 which come with a charger. Worked better than GoPro's batteries. They also stand behind their product. I'm sure their Sony NP-BX1 battery set works great too and at a great price.

You apparently missed my point yesterday as well as again today when I made the same point again, so I will repeat it below, and then further explain / clarify it:



L Copps wrote:

"I worked in an authorized Sony repair shop (not cameras) for years. Every decent quality battery powered device I ever saw included a voltage regulator that conditioned the power from the battery and was robust to regulate power from absurdly high levels. I have used aftermarket batteries for many years and never had an oversupply problem. Some of them ran down way too fast, but that was the only downside I have ever seen"

and my reply stated:



"The protective design protects primarily against overheat when charging, NOT during in-camera use / discharge, although it could be also used in this manner as well."



The correctly and safely designed battery contains a thermistor to sense internal temperature to report back to the charger. It is not the charger or any voltage regulator in the charger which is "the protective design". It is the temperature sensor in the battery which dictates how much energy the charger is allowed to create by current limiting the output. The battery itself can and will cause a fire or rupture hazard, possibly in a violent manner, if this thermistor is replaced with a fixed, non-temperature sensing resistor, or, worse yet, is eliminated entirely, as is the case for the cheaper battery under discussion. I made no statements whatsoever about "ruining the camera", although the fact that the generic battery lacks any thermistor can result in excessive temperature rise in the charging cycle if the camera is given misleading feedback from the battery, or, as my first reply to you indicated, could fail to shut the camera down under temperature conditions which are unsafe during camera recording or playback. It is very common for such conditions to occur from sensor overheat, heat-soaked camera exposure to direct sunlight for extended periods, etc.

Maybe the simplest and best way to restate this is simply to say that the battery is just one element of a system designed to work together safely and reliably, and cheap generic batteries eliminate the crucial temperature sensor to save a few cents in manufacturer thus disabling this safety feature.

Not sure what you mean by "the Physics of the chemistry" but I assure you that voltage regulation on the charger is only a partial explanation of how battery and charger safety are actually considered by engineers who do the designs. The lack of temperature sensing means that the battery can and will overheat under some conditions, and then the only remaining safeguard is the integrity of the vents and the strength of the case, both of which need to contain the overpressure or allow it to dissipate in a controlled and vented manner. The really cheapo designs use a slow, low current charging technique to avoid this issue, and never raise the internal temperature as much. This is done by extending the charging time a great deal, something many people do not like but others do not care about. Note that these are not voltage regulated as you stated, but rather are current limited.

The Physics of the battery chemistry will not let it hold a charge that the camera's voltage regulator cannot handle. I also doubt the camera can discharge the battery with enough amperage to cause the battery to damage the camera. The only heat risk will come from charging in the camera.

You apparently are unaware of overcharging, one of the several tricky elements of how to manage a lithium ion battery. I suggest you might take a look at the technical article I previously cited, and see why the battery has to be brought through separate voltage and also current limited regions of the charging cycle. Also, lithium ion batteries have a notoriously flat discharge characteristic, such that terminal voltage alone is a poor / useless indicator of the state of charge. The faster / better / safer chargers commonly use a microcontroller / ASIC to do it properly. The cheap generic chargers may not, again to save on manufacturing cost. In lieu of a smart controller chip and supporting parts, the generics go for lower charging rates and thus longer charging times.



Larry

 

[LSHorwitz1]

Ron AKA wrote:

Did you know that the early Toyota Prius Hybrids ran on consumer C cells from Panasonic. They put a whole bunch in series as the hybrids use up to 245 volts DC, but not much current. Toyota bought the technology from Panasonic and I believe they now make a custom battery for the Prius and Camry hybrid, but it is still small like a C cell.

One might be surprised what they put in the Dreamliner...

Ron,



I hate to be a nay-sayer here (again) but the Prius electric motor makes about 30KW of power, drawing several HUNDRED amps in the process.

Typical consumer C cells, such as the Duracell, Energizer, etc. make about 6 amps for an hour to totally deplete.

If you merely wired a bunch of them in series only, you could only make a tiny fraction of the current which is required, about 1.6%.

The closest you could come with such batteries would require roughly 200 series wired sets of about 60 batteries apiece, for a total of 12,000 batteries, which would power the electric portion of the Prius for one hour, give or take, before needing to be pulled out and replaced.



http://www.electrifyingtimes.com/priustechspecs.html



http://www.zbattery.com/zbattery/batteryinfo.html



Larry

 

[Ron AKA]

It is the temperature sensor in the battery which dictates how much energy the charger is allowed to create by current limiting the output.

While technically this is possible, I would be suspicious that the charger in the RX100 is not that sophisticated. Much more likely it is a high limit device and shuts the charging down if it detects a temperature over a certain value.

 

[Ron AKA]

LSHorwitz1 wrote:

I hate to be a nay-sayer here (again) but the Prius electric motor makes about 30KW of power, drawing several HUNDRED amps in the process. Typical consumer C cells, such as the Duracell, Energizer, etc. make about 6 amps for an hour to totally deplete.

Sorry I was going from memory. They used D cells in the original Prius battery, not C cells. There were 40 modules with 6 D cells in each module wired in series to give 7.2 volts per module and 288 volts for the complete battery pack. Not sure of the capacity of the original but later Prius versions have a capacity of 6.5 Amp-hours for the complete pack. They are now using prismatic cells to save space.

The actual motor generators operate on AC at about 600 volts, so there is an inverter and rectifier between the MG's and the battery.

Prius History

 

[lester11]

The Prius Hybrid doesn't run for long just on the battery, and certainly nowhere near one hour. My Prius (3rd generation) will flatten its battery after around 4 minutes with electric-only power at 20 mph.

Wikipedia tells us power (for 2nd generation) is given by a

"38-module NiMH battery pack providing 273.6 volts, 6.5 A·h capacity and weighing 53.3 kg (118 lb) is supplied by Japan's Panasonic"

Its a 6500 mAh capacity pack...! So, around 360 Sony NP-BX1 cells would do the trick for about half the weight...

http://en.wikipedia.org/wiki/Toyota_Prius

--
Lester

 

[LSHorwitz1]

Ron AKA wrote:

It is the temperature sensor in the battery which dictates how much energy the charger is allowed to create by current limiting the output.

While technically this is possible, I would be suspicious that the charger in the RX100 is not that sophisticated. Much more likely it is a high limit device and shuts the charging down if it detects a temperature over a certain value.

Ron,



If you are saying that the charging taper / top-off of the battery is not determined by the thermistor, I think you are right. The properly designed chargers use a microcontroller / application specific IC / ASIC to handle this properly. I would expect the camera to include such a circuit, and also that a correctly designed external charger would as well.



I would not, however, expect to find it necessarily in a generic charger. Hence my concern.

 

[LSHorwitz1]

lester11 wrote:

The Prius Hybrid doesn't run for long just on the battery, and certainly nowhere near one hour. My Prius (3rd generation) will flatten its battery after around 4 minutes with electric-only power at 20 mph.

Wikipedia tells us power (for 2nd generation) is given by a

"38-module NiMH battery pack providing 273.6 volts, 6.5 A·h capacity and weighing 53.3 kg (118 lb) is supplied by Japan's Panasonic"

Its a 6500 mAh capacity pack...! So, around 360 Sony NP-BX1 cells would do the trick for about half the weight...

http://en.wikipedia.org/wiki/Toyota_Prius

 

[Ron AKA]

lester11 wrote:

Its a 6500 mAh capacity pack...! So, around 360 Sony NP-BX1 cells would do the trick for about half the weight...

Yes, that is the reason for interest in Lithium Ion in automobiles and airplanes. Li-Ion are more compact and store more energy for the weight. Toyota, unlike Boeing, Hyundai, and Ford are resisting the change from NiMH to Li-Ion though. They maintain that NiMH give longer more reliable life in the constantly charging and discharging service of a hybrid battery. Given they are forced to offer long term warranties on their hybrid batteries, they have reason to be concerned. Also there is not any significant advantage in offering more battery capacity in a pure hybrid after a certain point. All the energy in a hybrid is derived from gasoline, and the battery is just a very short term buffer to store energy. Many hybrid owners think incorrectly that they are getting some free electrical energy from "somewhere", and if they had a larger battery their car would become more efficient and cheaper to run. Not true.

I drive a 2012 Camry Hybrid and even though it is a lot more powerful than a Prius it still only has a 6.5 Amp hour battery. The claimed motor output is 104 kW, but still just uses 204 1.2 volt cells connected in series. Essentially 102 D cell flashlights!