PART TWO: EXTENDED FIELD TEST, Cinq5 SMart Power Pack IIAS A POWER SUPPLYWhile the SPP is primarily intended as a buffer battery to take up the slack in supplying power while stopped briefly or riding at slow speeds, it also works as an external battery capable of powering or extending the life of gadgets plugged into it.
When used this way, it is important to remember to turn the unit on, or no power will be supplied! This is different from my other sources that start as soon as they are plugged in. The SPP is truly on or off depending on switch position, and this aids self-charging while wired as a buffer battery, independent of its powering other devices.
The power source is a Lithium-ion pile rated at >3,000mAh. In drain-down _tests_, I was consistently able to confirm 2,950mAh. Though the battery has circuitry to prevent damage from over-charging and deep-discharging, I decided not to risk going further. In _touring_ as a buffer battery, I generally used the SPP conservatively -- until the LED battery indicator first showed "red", meaning between 0-40% charge remaining. This left some remaining capacity for use as a supplemental battery in camp use. I never used it to the point where it shut down.
My Samsung Galaxy S4 smartphone's OEM battery is rated at 2600mAh capacity. I had no trouble recharging it from 15% remaining charge (the point at which a warning to charge appears on the phone) to full using the SPP. It is fair to think of the SPP as a "doubler" for my phone's battery. As for directly powering the phone, the SPP had no trouble meeting the phone's variable current demands, all of which fell well within its 1500mA capacity. It will also recharge a tablet of this capacity. I was able to confirm in testing: No special cable is needed to recharge an iPhone 5. The SPP will charge a 5.0vdc USB-powered device so long as the power draw doesn't exceed 1.5A or 7.5W (7.5Watts = 1.5A x 5.0vdc).
Serving as a standalone power supply/external battery/booster battery is a happy byproduct, but where the SPP really shines is as a buffer battery, supplying intermittent power to a bicycle-powered device during those brief times the bicycle is going too slowly to charge the device or is stopped, as at a traffic signal or when taking photos and drinking, snacking, or resting. For long-term standalone power of my gadgets in camp, I prefer to use either the 5,400mAh accumulator batteries in my solar panels or my mains-chargeable 22,000mAh external battery, simply because they offer greater capacity and longer run-times/more charges.
AS A BUFFER BATTERYIn use, I found the SPP to work well as a buffer battery, supplying constant power to my devices as my speed dropped or while stopped at traffic lights and it did prevent those devices from turning off or going under-voltage. I avoided the annoyance of having to manually turn devices back on after stopping -- they continued to run because they had a constant power supply whether I was riding or stopped.
This is a key point valid for all buffer batteries: They can serve as buffer batteries only as long as they are charged and so long as they can supply the needed current. The good news is, most devices meeting USB 2.0 standards (~5vdc @ ~500mAh within defined tolerances) are powered diectly from the bicycle dyno-powered charger except when power goes too low or when stopped. That's when the battery kicks in to serve as a buffer against loss and keeps the device going. This use is intermittent and short-term, so the battery can be expected to last a reasonable amount of time between charges in this sort of use unless one stops for an extended period of time. If the device doesn't draw too much current, the buffer battery can also charge as current passes through it.
Of course, even high-draw devices can be charged more readily if they are off, drawing minimal power. When running, a device may not draw a constant load, and its demands will be much greater than when off or in an idle state. For example, a cellphone running a GPS app and recalculating the route with the screen set at full brightness for daytime use will draw more current than when it is off. Some charging profiles are non-linear as well, with the device initially drawing more current then easing off in its demands as the battery nears full capacity.
The problem comes when the device to be charged draws more energy
to charge or
in use than what the bicycle charger alone can supply. In this situation the buffer battery -- if it has the capacity -- will make up the difference for as long as it contains a charge. In other words, if the device being powered has power requirements exceeding what the bicycle charger can supply, the buffer battery becomes a power supply to the extent it can make up the difference.
At the other end, power from the dynohub passes through the SPP, so if the demand on it is not high or continuous -- and it is set for low-current charging -- it can maintain a charge longer or even gain a charge itself.
CAPACITYSo, how large is the SPP's battery capacity, and will it power your device? Cinq5 literature rates it at more than 3,000mAh, capable of providing about 4 watt-hours of discharging at USB specification (5vdc @ 500mA).
I was able to check and verify this claim.
We know lithium-ion batteries have a cell voltage of 3.7volts. Working backward, if the lithium ion battery has a _cell capacity_ of = 3000mAh at a nominal voltage of 3.7V, then it should have a capacity of 3A*3.7v=11.1W (batteries used three in a series) -- and it does, as confirmed by TT/Cinq5. A standard USB specification would result in 0.5A*5.0v=2.5W, so even just 10Wh would indeed result in 4 hours of operation for a USB 2.0-spec device drawing 2.5W. TT/Cinq5 have simply rated the SPP conservatively to avoid disappointment and to ensure it will provide at least the full promised power.
To see how long your device can be powered by the SPP, just convert mAh (milliamp-hours) to watts. The reason for the conversion is the commonly-used amp-hour rating just measures the current available for an hour and is therefore a measure of *current capacity*, not *energy capacity*, as watts is. Different battery technologies provide different levels of energy capacity. Two batteries rated for different amp-hours may supply different amounts of energy, so amp-hour conversions only work for charging between the same types of batteries. Converting to watts makes for a direct comparison. To figure power, the equation is Watts = amps*volts. For energy, Watt-hours = amp-hours*volts. To convert from amp-hour or milliamp-hour ratings to watt-hours, simply multiply Amp-hours by the voltage of the power pack (Ah*v=Wh). Compare the result to the TT/Cinq5 SPP watt-hour figures and you'll know how long it alone can power your device. The SPP will of course last much longer as a buffer battery because the demand on it is not continuous.
The most common batteries you'll likely be charging are:
• Li-ion (Lithium-ion) @ 3.7v/cell, typically ganged in packs of 3 in series for a total of 11.1v.
• Li-po (lithium-ion iron phosphate) @ 3.2v/cell, typically packed 4 cells in series totaling 12.8v.
• NiMH (Nickel-metal Hydride) and NiCad (Nickel-cadmium) as individual cells, but you can count how many are used or charged at a time (typically in pairs). The voltage for these is 1.2v each. The Amp-hour ratings will usually be on the label.
I was left with some remaining questions I could not answer in testing, so I put them to ToutTerrain/Cinq5:
Q. How many charges is the SPP rated for before the battery is permanently exhausted or won't take a charge?
A. Minimum 500 total charge/discharge cycles from total empty to full. For example, two half charges are one total cycles.....!?
Over the time, the cell will shade continuous some capacity, but we are using high quality cells from Panasonic, so this effect will be very slow.
Q. Can it/must it be stored with a charge?
A. Should be stored with 75% charged.
Q. If it is stored in a discharged state, can it be damaged?
A. Yes it can, but it depends on the time the battery is not used.
Q. Does the battery have LSD (Low Self-Discharge) characteristics? How long will it hold a charge?
A. Yes, the battery has LSD. The battery can be not used for a year if it is fully or nearly fully charged.
Q. In use the battery is in a constant state of charge/discharge, depending on the speed of the bicycle. Do these dis/charge cycles ultimately affect battery life?
A. This does affect the battery life in the same way as a normal use like charging and discharging (no memory effect at the Li-ion Cells) The thing is you are charging and discharging every time in the same level depending on the charging/discharging mode. 100 mA/400mA/900mA constantly
IS THE SPP PERFECT? NO, BUT MUCH CLOSER THAN OTHER OPTIONS AT PRESENTIn my tests and opinion, the SPP as the best available buffer battery of those I've tried to date, primarily due to its adjustable self-charging rate and its capacity to charge high-draw devices, but I would like to see some improvements for the next version:
• A user-replaceable battery. Given the quality of the aluminum housing and the price, it would be nice to have the device continue beyond the original battery service life. As an alternative, perhaps a mail-in reconditoning service or trade-in program could be introduced to reduce cost and environmental impact and extend service life.
• Weather sealing for all the USB connector plugs via a flexible rubber bellows or boots so charging/power supplying to gadgets can continue in foul weather without need to place them under cover and without inerruption due to weather. Inverting the SPP in its mount so the connections aim downward aids this goal.
• Development and availability of an elastic headband so the unit can be worn as a hands-free LED headamp for easier use in camp.
• A brighter, perhaps dimmable/boosted white LED for more versatile lighting on and off the bike at the expense of ultimate battery life.
• A square form-factor instead of a cylinder to reduce the tendency to roll when laid on a flat surface.
• Twist-cap, gasketed shielding of the USB ports allowing for extended splash resistace and perhaps even IPX7 submersion when not charging.
• Development of a larger-capacity version with the same low/adjustable charging thresholds for greater versatility as a standalone external battery. Perhaps this could be accomplished by buying two units so they could be charged individually from bicycle dynopower and in multiples when charged by mains power.
• Greater temperature isolation between the black-anodized housing and the battery/circuitry or as a sleeve to allow operation in a wider temperature range. Unfortunately, this would result in a larger and heavier unit. Black-anodized aluminum is beautiful and durable, but also a great temperature conductor, making the unit hot to touch after sitting in sunshine and cold on cold days, so perhaps a thin outer sleeve or dip-coating would be better.
• Clear labeling of the charge rates/LED displays on the case so a separate reader card is not required...or printing the information on a sticker that can be placed on each unit, or even laser-etching it on the unit itself.
CONCLUSIONI have now used the Cinq5 Smart Power Pack for just over 2 months in a variety of real-world touring conditions, from desert sandstorms to rain and freezing rain in temperatures as low as -8°C/17°F, and warmed to 51°C/124°F. It held up well and fulfilled its promise as a practical buffer battery for my gadgets. For my use, The Cinq5 Smart Power Pack II addresses the shortcomings present in most buffer batteries and is unique in being one of only a few buffer/external batteries on the market that are bicycle-specific and is supplied with mounting solutons for that use. It offers flexible charging programs to charge itself with low-power inputs common when riding slowly with a bicycle dyno-charger or direct from solar power.
At the same time, it has sufficient capacity to directly power or serve as a buffer for high-demand devices like smartphones and GPS units. Like all external and buffer batteries, it won't power devices indefinitely, but has sufficient capacity to work throughout a typical touring day and can then be recharged from a variety of sources ranging from solar power to bicycle dynopower, computer USB ports and smartphone chargers.
As an added value, it includes convenient camp and emergency/signal lighting in the same unit and a compact, easily de/mountable form. Though costly as befits a premium product, I found it worked well and reliably in demanding use and it proved durable in rough conditions. It is best suited for those who need charging/powering of devices at slower speeds and need to power high-drain devices like smartphones and GPS units continuously while cycling.
The Cinq5 Smart Power Pack II is available from the Cinq5 online store for €99.00 incl. VAT plus delivery.
See:
http://shop.cinq5.de/epages/es984127.sf/en_GB/?ViewObjectPath=%2FShops%2Fes984127The X-mount is a recommended accessory available separately for €9.90 incl. VAT plus delivery.
See:
http://shop.cinq5.de/epages/es984127.sf/en_GB/?ObjectPath=/Shops/es984127/Products/%22Smart%20Power%20Pack%20Halterung%20x-Mount%22The Cinq5 Smart Power Pack II is available from St John's Street Cyclery for €106.71
See:
http://www.sjscycles.co.uk/cinq5-smart-power-pack-ii-prod32694/?currency=eur&geoc=usThe X-mount is available from St John's Street Cyclery for €11.29
See:
http://www.sjscycles.co.uk/cinq5-smart-power-pack-universal-h-handlebar-mount-prod32696/?currency=eur&geoc=us