HP F4809A Battery Care
Thank you for purchasing a HP F4809A Battery . This page contains information that you can print now or refer to in the future to get maximum performance from your HP F4809A Battery .
Table of Contents
How to Maximize the Lifespan of your HP F4809A Battery
Follow these simple steps to maximize the life of your HP F4809A Battery :
- Charge the Li-ion battery often, except before a long storage. Avoid repeated deep discharges.
- Keep Li-ion batteries cool. Prevent storage in a hot car. Never freeze a battery.
- If your laptop is capable of running without a battery and fixed power is used most of the time, remove the battery and store it in a cool place, with about 50% charge. Do not store fully charged or fully discharged. Remember, heat is not good for batteries, and your laptop operating temperature exceeds 45 degrees celcius.
- Exercise your battery. Ltihium Ion Batteries might not have memory, but they do need exercise once in awhile to remain in tip top shap. Don't let your new HP F4809A Battery die an early death from laziness!
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Quality Assurance
Each and every UpStart Battery sold, including your new HP F4809A Battery , is primed and tested with the leading battery analyzers on the market today. This equipment is extremely effective in eliminating manufacturing defects before shipping product to a customer in the first place. It is also very effective in improving battery performance, especially for older, Nicad batteries. Our analyzers are also useful in eliminating excessive passivating layers for lithium ion batteries that have stored for extended periods in a charged/discharged state.
This level of testing is critical, yet not normally performed by after market battery manufacturers. This is one of the ways that UpStart Battery is unique, and why you should pat yourself on the back for buying your HP F4809A Battery from us.
Let us explain.
Even with modern manufacturing techniques, the capacity of a cell cannot be accurately predicted. As part of the manufacturing process, each cell is measured and segregated into categories according to their inherent capacity levels. The high capacity A cells are commonly sold for special applications at premium prices; the large mid-range B cells are used for commercial and industrial applications such as mobile communications; and the low-end C grade cells are mostly sold as discards to low end pack manufacturers. There is no way to significantly improve the capacity of the low-end cell. When purchasing rechargeable batteries at a reduced price, the buyer should be aware of the different capacity and quality levels available. All UpStart Batteries, including your HP F4809A Battery , are made only with premium grade A cells. They cost much more than the discards, but our customers are worth it.
As part of quality control, battery assemblers should spot-check each batch of cells to examine cell uniformity in terms of voltage, capacity and internal resistance. Failing to observe these simple rules will often result in premature battery failures.
Another quality problem in pack manufacturing is the issue of electrical shorts. The suspected culprit is foreign particles that contaminate the cells during manufacture. Another possible cause is rough spots on the plates that damage the separator. Better quality control at the raw material level and minimal human interface during the manufacturing process has greatly reduced the ‘infant mortality’ rate of the modern rechargeable cells, but this is still one of the factors that separates A grade cells from B or reject grade cells.
Replacing a shorted cell in an aging pack is not recommended unless the new cell is matched with the others in terms of voltage and capacity. Otherwise, an imbalance may occur. See the section on Cell Mismatch below.. Attempts to replace faulty cells have commonly led to battery failures after about six months of use. It is best not to disturb the cells in a battery pack but allow them to age naturally. Maintaining the batteries while they are still in good working condition will help to prevent premature failure.
Shorts in a Li-ion cell are uncommon. Protection circuits monitor an ailing Li-ion cell and render the pack unusable if serious voltage irregularities are detected. Charging such a pack would (protection circuit permitting) generate excess heat. The battery’s temperature control circuits are designed to terminate the charge. It is for this reason that poor quality after market cells seem to "work fine" - until suddenly they don't work at all.
A properly designed, correctly charged Li-ion cell should never generate or vent gases. However, lithium based cells can build up internal pressure under certain conditions. Provisions are made to maintain safety of the battery and equipment should this occur. Some cells include an electrical switch that opens if the cell pressure reaches a critical level. Other cells feature a membrane that safely releases the gases if need be. Controlled release of the pressure prevents bulging of the cell during pressure buildup. Most of the safety features of lithium-based batteries are one-way; meaning that once activated, the cells are inoperable thereafter. This is done for safety reasons.
Cell Mismatch
Your HP F4809A Battery , like most lithium ion battery packs, contains a number of cells all operating together like a synchronized swimming team to deliver the performance you expect. When these cells do not match, serious problems will result.
Cell mismatch can be found in brand-new as well as aged battery packs. Poor quality control at the cell manufacturing level and inadequate cell matching when assembling the batteries cause unevenly matched cells. If only slightly off, the cells in a new pack adapt to each other after a few charge/discharge cycles, like players in a winning sports team.
A weak cell holds less capacity and is discharged more quickly than the strong one. This imbalance causes cell reversal on the weak cell if the battery is discharged below 1V/cell. The weak cell reaches full charge first and goes into heat-generating overcharge while the stronger cell still accepts charge and remains cool. In both situations, the weak cell is at a disadvantage, making it weaker and contributing to a more acute cell mismatch condition. An analogy can be made with a high school bully who picks on the weaker kid.
High quality cells are more consistent in capacity than lower quality counterparts. During their life span, high quality cells degrade at about the same rate, helping to maintain the matching. Manufacturers of power tools choose high quality cells because of their durability under heavy load conditions and temperature extremes. Lower-cost cells have been tried, but early failure and consequent replacement is costlier than the initial investment.
The capacity matching between the cells in a battery pack should be within +/- 2.5 percent. Tighter tolerances are required on batteries with high cell counts that also must generate high load currents and are operating under adverse temperatures. There is a strong correlation between well-balanced cells and the longevity of a battery.
Lithium-based cells have even tighter matching tolerances than older technology batteries. Tight matching of all cells in a pack is especially important on lithium-based chemistries. All cells must reach the end-of-discharge voltage threshold at the same time. The full-charge point must be attained in unison by all cells. If the cells are allowed to get out of match, the weaker cell will be discharged to a lower voltage point before the cut-off occurs. On charge, this weak cell will attain the full-charge status before the others, causing the voltage to go higher than on the stronger cells. This larger voltage swing will put undue strain on the weak cell, causing the pack to fail prematurely.
Each cell in a lithium-based pack is electronically monitored to assure proper cell matching during the battery’s life. An electronic circuit is added to some packs that compensate the differences in cell voltages. This is done by connecting a shunt across each cell string to consume the excess energy of the cells which are more energetic. The low-voltage cut-off occurs when the weakest cell reaches the end-of-discharge point.
The Li-ion battery is controlled down to the cell level to assure safety at all times. Because this chemistry is still relatively new and unpredictable under extreme conditions, manufacturers do not want to take undue risks. There have been a few failures but such irregularities are often kept a secret. Those that are not successfully kept secret often fail with spectacular results - explosion or fire. Just search YouTube for lithium ion battery to see for yourself what can happen when poor quality cells are used..
Lithium Ion chemistry is considered very safe, considering the large number of Li-ion batteries that are in use. But due to the safety risks, even though remote, the folks at UpStart Battery decided from day one to use only grade A cells in their battery pack construction. The key to this quality is the special relationship that UpStart Battery has with the OEM manufacturers. Due to trademark and nondisclosure reasons, we cannot name the other brands that are made in UpStart Battery factories. However, run an internet search for "top 10 portable electronic brands" or similar. Batteries for three or more of those brands are made in the same factory as UpStart Battery. And UpStart Battery is the only non-OEM brand to come from those same factories. UpStart Battery signs exclusive distribution agreements for the replacement market. Your UpStart Battery Brand HP F4809A Battery came from a certified OEM factory, using only grade A cells. It is this level of quality that separates UpStart from the competition in the resale market, and allows us to offer you a lifetime warranty on your battery.
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HP F4809A Battery Performance Characteristics
All batteries experience a decline in performance over the years, and your new HP F4809A Battery will be no different. Although fully charged, the battery eventually regresses to a point where the available energy is less than half of its original capacity, which can result in unexpected downtime.
It is commonly noted that batteries can experience a memory effect. However, new lithium ion technology in use in your HP F4809A Battery will ensure that this never is a problem for you. The continuing confusion reflects older technology such as nicad or nimh that is now considered obsolute in most, but not all, applications. The folks at Duracell described the memory effect best: “The voltage drop occurs because only a portion of the active materials in the cells is discharged and recharged during shallow or partial discharging. The active materials that have not been cycled change in physical characteristics and increase in resistance. Subsequent full discharge/charge cycling will restore the active materials to their original state.”
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The Memory Effect
The memory effect is primarily associated with older, obsolete NiCad batteries. It refers to the apparent behavior that a NiCd battery can remember how much discharge was required on previous discharges. Improvements in battery technology have virtually eliminated this phenomenon.
Lithium and lead-based batteries are not affected by memory, but these chemistries have their own peculiarities. Current inhibiting passivating layers affect both batteries — plate oxidation on the lithium and sulfation and corrosion on the lead acid systems. These degenerative effects are only partially reversible on the lead acid battery, and there is some controversy as to whether or not the effect is permanent in Lithium Ion or lithium polymer batteries.
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Passivating Layers and your HP F4809A Battery
Lithium Ion batteries are manufactured using a lithium oxide cathode and a carbon based anode. Lithium ions travel through a non aqueous medium during charge and discharge. These batteries have a half life of about 1000 charge cycles (50% charge retained at 1000 charge/discharge cycles).
Lithium batteries retain their state of charge (10% loss per month) much longer than earlier technologies partially because a thin passivating layers forms on the electrode surfaces. The chemical composition of the passivating layer varies with battery construction chemistry. These variations in battery chemistry are closely guarded competitive secrets, and is one of the key reasons that UpStart Batteries, such as your HP F4809A Battery , last so long. The presence of a passivating layer can be problematic if it grows to more completely block the anode and/or cathode. Passivation thickness increases with increased storage time, temperature, and state of charge.
The presence of a passivating layer ( essentially a high resistance) always results in a voltage dip from the battery when a load is applied. The magnitude and period of the dip is a function of the passivation thickness. The layer thickness is decreased as a function of coulombs transferred from the battery. This layer forms every time you stop using a battery. The layer is removed every time you use the battery.
If the voltage drop is great enough, it is possible that your computer will shut itself off. This is a normal function in laptop electronics. If this does happen, the passivation layer can be removed by putting a pure resistive load on the battery until the passivation layer is removed. What that effectively means is that the passivating layer can be removed by shorting out the battery. This action is extremely dangerous, and can result in overheating, fire, and explosion. Due to legal liability reasons, we cannot provide any additional information on how to eliminate the passivating layer by applying a resistive load. Suffice to say that we do not recommend it. Certain things, such as heart surgery, space travel, and lithium ion battery repair should only be attempted by higher skilled engineers in a proprer lab. Please do not attempt this procedure on your HP F4809A Battery .
Avoiding the development of excessive passivating layers is simple: don't store your HP F4809A Battery for extended periods in a fully charged state. If you want to store your battery, best to leave it with approximately 50% battery life. If you know you want to store your battery for awhile, simply discharge the battery to approximately half its normal life by using your computer as normal (unplugged, of course!). You can now remove your HP F4809A Battery and store it safely without concern. In fact, if you always use your laptop with the AC Adapter plugged in, we recommend that you do remove and store the battery. Pull it out and charge / discharge the battery again every few months to ensure that your passivating layers do not get too thick. By following these techniques, your HP F4809A Battery should last until, well, until you don't care anymore! And because it is a genuine UpStart Battery, you have a Lifetime Warranty.
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Self Discharge
The self-discharge of the Li-ion battery is five percent in the first 24 hours after charge and averages 1 to 2 percent per month thereafter. In addition to the natural self-discharge through the chemical cell, the safety circuit draws as much as 3 percent per month. High cycle count and aging has little effect on self-discharge on lithium-based batteries.
Heat has the most affect on lithium ion batteries. A fully charged Li-ion battery that is stored at 45°C suffers a capacity loss from 100 percent to about 70 percent in as little as six months. If this condition persists, the capacity degrades further to 50 percent in twelve months.
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Battery Storage
Batteries are a perishable product and start deteriorating right from the time they leave the manufacturing plant. For this reason, it is not advisable to stock up on batteries for future use. This is especially true with lithium-based batteries. The buyer should also be aware of the manufacturing date. Avoid acquiring old stock.
Keep batteries in a cool and dry storage area. Refrigerators are recommended, but freezers must be avoided because most battery chemistries are not suited for storage in sub-freezing temperatures. When refrigerated, the battery should be placed in a plastic bag to protect it against condensation.
Lithium Ion batteries do not like prolonged storage. Irreversible capacity loss occurs after 6 to 12 months, especially if the battery is stored at full charge and at warm temperatures. Running a laptop (or other portable device) continuously on an external power source with the battery engaged will have the same effect.
The combination of a full charge condition and high temperature cannot always be avoided. Such is the case when keeping a spare battery in the car for a mobile phone. NiMH and Li-ion chemistries are severely affected by hot storage and operation.
|
| Temperature |
40% charge level
(recommended storage charge level) |
100% charge level
(typical user charge level) |
|
| 0°C |
98% after 1 year |
94% after 1 year |
| 25°C |
96% after 1 year |
80% after 1 year |
| 40°C |
85% after 1 year |
65% after 1 year |
| 60°C |
75% after 1 year |
60% after 3 months |
|
This chart shows the capacity remaining on Li-ion batteries after storage. Note that this is the functional capacity - the battery cannot be restored if stored fully charged under conditions of hot temperatures. Although your HP F4809A Battery is of premium quality, it is still subject to the same physical limitations of the technology. To make it last, keep it cool, and don't store it fully charged.
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Battery Charging
The Li-ion charger is a voltage-limiting device similar to the lead acid battery charger. The difference lies in a higher voltage per cell, tighter voltage tolerance and the absence of trickle or float charge when full charge is reached.
While the lead acid battery offers some flexibility in terms of voltage cut-off, manufacturers of Li-ion cells are very strict on setting the correct voltage. When the Li- ion was first introduced, the graphite system demanded a charge voltage limit of 4.10V/cell. Although higher voltages deliver increased energy densities, cell oxidation severely limited the service life in the early graphite cells that were charged above the 4.10V/cell threshold. This effect has been solved with chemical additives. Most commercial Li-ion cells can now be charged to 4.20V. The tolerance on all Li-ion batteries is a tight +/-0.05V/cell.
The charge time of all Li-ion batteries, when charged at a 1C initial current, is about 3 hours. The battery remains cool during charge. Full charge is attained after the voltage has reached the upper voltage threshold and the current has dropped and leveled off at about 3 percent of the nominal charge current.
Some chargers claim to fast-charge a Li-ion battery in one hour or less. However, you should be aware that such a charger declares that is "ready" (green light) when the charge level is about 70 percent. The topping charge typically takes twice as long as the initial charge. ie: getting it to 100% would take about three hours, eliminating the so called benefit of a "fast charger" for lithium ion batteries.
It is not recommended to discharge a battery before each charge because this wears down the battery unnecessarily and shortens the life. Neither is it advisable to leave a battery in the charger for a long period of time. When not in use, the battery should be put on a shelf and charged before use. Always store the battery in a cool place.
Li-ion batteries are designed to operate safely within their normal operating voltage but become increasingly unstable if charged to higher voltages. On a charge voltage above 4.30V, the cell causes lithium metal plating on the anode. In addition, the cathode material becomes an oxidizing agent, loses stability and releases oxygen. Overcharging causes the cell to heat up.
Much attention has been placed on the safety of the Li-ion battery. Commercial Li-ion battery packs contain a protection circuit that prevents the cell voltage from going too high while charging. The typical safety threshold is set to 4.30V/cell. In addition, temperature sensing disconnects the charge if the internal temperature approaches 90°C (194°F). Most cells feature a mechanical pressure switch that permanently interrupts the current path if a safe pressure threshold is exceeded. Internal voltage control circuits cut off the battery at low and high voltage points.
Most of the YouTube videos that you see showing 'exploding' lithium ion cells have been purposely forced into an unsafe state by purposely damaging or modifying the battery packs or chargers. Any battery can be forced to self destruct, just like any car can be purposely driven into oncoming traffic to create carnage and distruction. Safety and quality of construction is critically important, but can never compensate for malicious misuse.
We promise that your UpStart Battery brand HP F4809A Battery can be charged safely with your existing charger.
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Battery Recycling
Years from now, when you finally stop using your HP F4809A Battery , be sure to recycle it. Odds are, your UpStart Battery will still be in good working condition, but you have decided to upgrade to new equipment. When this day comes, please drop off your HP F4809A Battery for recycling at one of our 30,000 recycling centers across the nation. You can also send it to Certified Battery if you prefer and we will recycle it for you.
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Lithium Battery Travel Restrictions
There has been much recent confusion and press about the changes in regulations governing air travel and lithium batteries. Most people are not affected by this change in regulations as they do not understand the difference between primary lithium batteries, which are not rechargeable, and secondary lithium batteries like those including in laptops and cell phones. Your new HP F4809A Battery is not affected by these changes in air travel regulations.
There is an extensive posting at The Tasp and Droud Blog that explains this in detail, but we have reprinted it below.
There has been a lot of press going around about the new travel restrictions on lithium batteries. Unfortunately, much of the press doesn’t understand the technology and what it really means to the average traveler.
First, here is the link to the DOT press release on the new rules.
These regulations are an adoption of international hazerdous goods shipping norms within the US passenger market.
These regulations are focused primarily on lithium primary cells - batteries that use lithium metal and are not rechargeable. Some cameras use these in formats such as CR3 and others. The button cells in watches are also primary lithium batteries. People buying EnergizerLithium e2 AA/AAA batteries for their cameras will also be affected by these regulations. The other uses for lithium primary cells include high power flashlights and security systems.
These regulations are not focused on rechargeable lithium ion and lithium polymer batteries, except for those extremely high in capacity. This means that a person using cell phone batteries, standard size laptop batteries, and other similar devices will not need to be concerned about these new regulations.
There is a cap on the size of rechargeable lithium ion batteries allowed, although your average person will not be able to effectively calculate whether or not their device would be affected by these regs. Batteries with more than 8 grams, but less than 25 grams of equivalent lithium metal are considered “Extended Capacity Batteries”. Passengers are restricted to two of these type of batteries in their carry on bags. Batteries with greater than 25 grams of equivalent lithium content will not be allowed on the plane, and must be shipped as a hazerdous good.
Here is how you calculate equivalent lithium content:
Watt Hours * 0.3 X * number of cells in the battery pack
The problem for the average consumer is that they don’t know how many cells are in their battery pack unless they take it apart. Doing so would likely damage the pack casing, and is potentially dangerous.
The good news is that the largest battery you are likely to use would be one of the the 8800 mAh capacity batteries found in some notebooks. These packs usually have either eight or 12 cells, each rated between 2400mAh and 2000mAh.
Therefore, a 12 cell 2000mAh pack will have the following equivalent lithium content (to calculate watt hours, just divide the mAh by 1000):
12 * 2.0 * 0.3 = 7.2 grams of equivalent lithium metal. Therefore, no restrictions.
Notebook manufacturers are not stupid… they won’t make a pack that has travel restrictions on it, as the word would get out and people wouldn’t buy their laptops.
These new US FAA regs are extentions of existing international shipping norms that battery manufacturers have already been working with, so the end result is that most people will not be affected by these “new” regs in the slightest.
The only exception is the external extended batteries that people use for notebooks, dvd players and the like. Some of these are rated as high as 24000 mah. They will all have less than 25 grams of equivalent lithium, but you wouldn’t be allowed to take more than two of them. However, given that a battery of that size could power your laptop about 24 hours, odds are that a single one is all you would ever travel with anyway.
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Battery Conditioning
There is plenty of confusion surrounding the "conditioning" of lithium ion batteries. We have covered the topic elsewhere in this little guide, but here it is in a nutshell.
When people talk about Battery Conditioning they are referring to one of two possibilities. The first refers to the process of treating a battery in a "special" way in order to restore it to new, or nearly new life. The second possibility refers primarily to laptop and some camcorder batteries. In this case, the term "conditioning" has been misapplied by the marketing people of the computer and camera manufacturers. A better term would be battery calibration. In this case, there is a chip inside the battery that is read by software in the device, which then displays how much juice is left. The problem with this software is that over time, the actual capacity of the battery VS what the device "thinks" is the capacity of the battery become misaligned.
Resolving this is situation is quite simple. Simply consume all the power in the laptop or camera such that it shuts itself down (be sure that it doesn't just shut itself down due to a power saving mode). Then, recharge the battery fully. Presto! The software will be recalibrated. Note that this procedure does not increase the total available power, it simply improves the accuracy of your "power remaining display". You do not need to reconditon your new HP F4809A Battery unless your computer software becomes misaligned in this way over time.
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