Posts Tagged ‘thinkpad x60 tablet battery’

Laptop and Desktop Computer Batteries

March 21st, 2010

1. What are Main Batteries?

The main battery (also called the power battery) is the battery pack which allows a laptop or notebook to operate independently of an AC power source. These rechargeable batteries(thinkpad x60s battery , thinkpad x61s battery) are designed to operate the computer for a certain amount of time (generally 1 to 4 hours).

2. What are CMOS or Clock Batteries?

CMOS & Clock Backup batteries perform the same function in desktop and laptop computers: when the computer is turned off, the thinkpad x60 battery maintains the time and date, insuring their accuracy when the system is once again restarted. More importantly, the battery saves the computer’s CMOS set-up configuration, which allows the system to efficiently re-boot once it is restarted. The computer knows what type of hard drive it is dealing with, etc. Not surprisingly, these batteries are known alternatively as CMOS batteries, Real Time Clock (RTC) batteries, or simply internal batteries.

The most common CMOS battery chemistries are Lithium, Nickel Cadmium (NiCad) and alkaline. They are usually somewhere in the 3 to 7.2 volt range and either solder onto the motherboard or simply plug in via a snap-in connector (depending upon the computer manufacturer’s design).

In most cases, replacement of the CMOS battery is an easy task. It is simply a matter of locating the thinkpad x60 battery on the computer’s motherboard, removing it, and plugging in a new one. As a rule, internal batteries should be replaced by the same type of battery which was originally used in the machine, or according to the manufacturer’s specifications. The major exception to this rule are older IBM compatible computers which come with a NiCad battery soldered onto the motherboard. These computers usually have a three or four pin male plug, with two of the pins connected via a jumper (this is generally found in the same area of the motherboard as the original battery). This plug gives you the option of leaving the soldered battery in place and replacing it with a plug-in type battery. Removing the jumper tells the computer to ignore the battery soldered onto the motherboard and to look to the pins for its power source. IMPORTANT NOTE: NiCad batteries are rechargeable, whereas Lithium and alkaline batteries are NOT. Therefore, Lithium and alkaline batteries must be replaced by equivalent batteries of the same type. Attempting to replace these non-rechargeable batteries with a NiCad will result in a non-functioning battery, due to the fact the computer lacks the proper charging circuitry. If a motherboard lacks the above-discussed provision for an external battery, the NiCad battery MUST be unsoldered and replaced by a NiCad battery ONLY. Attempting to use an alkaline or lithium thinkpad x60s battery in place of NiCad on such a board could be hazardous. These batteries are not designed to be recharged, and an attempt to do so may cause the battery to “burst”, or explode.

CMOS batteries generally last for two to three years, although some (especially the lithium type) have been known to last much longer. Ironically, the less you use your computer, the faster the CMOS battery will run out. This is because when your computer is turned off the battery begins to function. It is recommended to replace the CMOS battery approximately once a year, or when servicing the computer. If your computer has been idle for an extended length of time it is a good idea to change the battery. Changing the thinkpad x60s battery is a relatively easy and inexpensive task, especially (as I’m sure many of you out there know) when compared to trying to reconfigure a computer which has lost its CMOS settings.

3. What are RAM or Resume batteries?

Some notebook computers are designed with a dedicated thinkpad x61s battery for backing up RAM functions when the machine is temporarily shut off. This feature allows users to change the main battery pack without losing the current applications and settings residing in RAM (Random Access Memory). This is called a “battery hot swap” – switching the main battery pack without having to turn off the computer.

These type of batteries are alternately known as bridge batteries, RAM batteries, or resume batteries.

Most RAM batteries are rechargeable NiCad and will last around 2-3 years. It is recommended that you replace your notebook’s thinkpad x61s battery when replacing the CMOS battery.

4. How Long Will the New Battery Power My Laptop?

That is difficult to determine. Actual thinkpad x40 battery running time depends upon the power demands made by the equipment. The use of the monitor, the hard drive and other accessories results in an additional drain upon the battery, effectively reducing its running time. The total running time of the battery is also dependent upon the design of the equipment. Generally, a new BatteryValues.com battery will run at least as long (and usually- longer) as your old battery did when it was new.

5. Is it Possible to Upgrade My Device’s Battery to a Newer Chemistry?

NiCad, NiMH and Li-ion are all fundamentally different from one another and cannot be substituted unless the device has been pre-configured from the factory to accept more than one type of rechargeable thinkpad x40 battery. The difference between them stems from the fact that each type requires a different charging pattern to be properly recharged. Therefore, the portable device’s charger must be properly configured to handle a given type of rechargeable battery.

Refer to your owner’s manual to find out which rechargeable thinkpad x40 battery types your particular device supports, or simply use our search engine to find your device. It will automatically list all of the battery types supported by your machine.

6. What is a “smart” Battery?

Smart batteries have internal circuit boards with smart chips which allow them to communicate with the notebook and thus better monitor battery performance, output voltage and temperature. Smart batteries will generally run 15% longer due to their increased efficiency and also give the computer much more accurate “fuel gauge” capabilities to determine how much thinkpad x41 battery running time is left before the next recharge is required.

7. How Can I Maximize Battery Performance?

There are several steps you can take to insure that you get maximum performance from your battery:

Breaking In New Batteries – new batteries come in a discharged condition and must be fully charged before use. It is recommended that you fully charge and discharge your new thinkpad x41 battery two to four times to allow it to reach its maximum rated capacity.

Preventing the Memory Effect – Keep your battery healthy by fully charging and then fully discharging it at least once every two to three weeks. Exceptions to the rule are Li-Ion batteries which do not suffer from the memory effect.

Keep Your Batteries Clean – It’s a good idea to clean dirty thinkpad x41 battery contacts with a cotton swab and alcohol. This helps maintain a good connection between the battery and your portable device.

Exercise Your Battery – Do not leave your battery dormant for long periods of time. We recommend using the battery at least once every two to three weeks. If a battery has not been used for a long period of time, perform the new battery break in procedure described above.

Battery Storage – If you don’t plan on using the thinkpad x60 tablet battery for a month or more, we recommend storing it in a clean, dry, cool place away from heat and metal objects. NiCad, NiMH and Li-Ion batteries will self-discharge during storage; remember to break them in before use. Sealed Lead Acid (SLA) batteries must be kept at full charge during storage. This is usually achieved by using special trickle chargers. If you do not have a trickle charger, do not attempt to store SLA batteries for more than three months.

For Notebook Users – To get maximum performance from your thinkpad x60 tablet battery, fully optimize the notebook’s power management features prior to use. Power management is a trade off: better power conservation in exchange for lesser computer performance. The power management system conserves battery power by setting the processor to run at a slower speed, dimming the screen, spinning down the hard drive when it’s not in use and causing the machine to go into sleep mode when inactive. Your notebook user’s guide will provide information relating to specific power management features.

8. How Long Do Batteries Last (What is the Life Span of My New Battery)?

The life of a rechargeable battery operating under normal conditions is generally between 500 to 800 charge-discharge cycles. This translates into one and a half to three years of thinkpad x61 tablet battery life for the average user. As your rechargeable battery begins to die, you will notice a decline in the running time of the battery. When your two hour battery is only supplying you with an hour’s worth of use, it’s time for a new one.

9. My New Battery Isn’t Charging. What’s the Deal?

New batteries are shipped in a discharged condition and must charged before use. We generally recommend an overnight charge (approximately twelve hours). Refer to your user’s manual for charging instructions. Rechargeable batteries should be cycled – fully charged and then fully discharged – 2 to 4 times initially to allow them to reach their full capacity. (Note: it is perfectly normal for a battery to become warm to the touch during charging and discharging).

New batteries are hard for your device to charge; they have never been fully charged and are therefore “unformed”. Sometimes your device’s charger will stop charging a new thinkpad x61 tablet battery before it is fully charged. If this happens, simply remove the battery from your device and then re-insert it. The charge cycle should begin again. This may happen several times during your first battery charge. Don’t worry; it’s perfectly normal.

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How to prolong lithium-ion laptop battery

March 3rd, 2010

Lithium-ion has not yet fully matured and is being improved continuously. New metal and chemical combinations are being tried every six months to increase energy density and prolong service life. The improvements in longevity after each change will not be known for a few years.

A thinkpad x40 battery provides 300-500 discharge/charge cycles. The battery prefers a partial rather than a full discharge. Frequent full discharges should be avoided when possible. Instead, charge the battery more often or use a larger battery. There is no concern of memory when applying unscheduled charges.

Although lithium-ion is memory-free in terms of performance deterioration, batteries(thinkpad x40 battery,thinkpad x41 battery) with fuel gauges exhibit what engineers refer to as “digital memory”. Here is the reason: Short discharges with subsequent recharges do not provide the periodic calibration needed to synchronize the fuel gauge with the battery’s state-of-charge. A deliberate full discharge and recharge every 30 charges corrects this problem. Letting the battery run down to the cut-off point in the equipment will do this. If ignored, the fuel gauge will become increasingly less accurate. (Read more in ‘Choosing the right battery for portable computing’, Part Two.)

Aging of lithium-ion is an issue that is often ignored. A thinkpad x60 battery in use typically lasts between 2-3 years. The capacity loss manifests itself in increased internal resistance caused by oxidation. Eventually, the cell resistance reaches a point where the pack can no longer deliver the stored energy although the battery may still have ample charge. For this reason, an aged thinkpad x60s battery can be kept longer in applications that draw low current as opposed to a function that demands heavy loads. Increasing internal resistance with cycle life and age is typical for cobalt-based lithium-ion, a system that is used for cell phones, cameras and laptops because of high energy density. The lower energy dense manganese-based lithium-ion, also known as spinel, maintains the internal resistance through its life but loses capacity due to chemical decompositions. Spinel is primarily used for power tools.

The speed by which lithium-ion ages is governed by temperature and state-of-charge. Figure 1 illustrates the capacity loss as a function of these two parameters.

Battery research is focusing heavily on lithium chemistries, so much so that one could presume that all portable devices will be powered with lithium-ion batteries in the future. In many ways, lithium-ion is superior to nickel and lead-based chemistries and the applications for lithium-ion batteries(thinkpad x60 battery,thinkpad x60s battery) are growing as a result.

Lithium-ion has not yet fully matured and is being improved continuously. New metal and chemical combinations are being tried every six months to increase energy density and prolong service life. The improvements in longevity after each change will not be known for a few years.

A thinkpad x60 tablet battery provides 300-500 discharge/charge cycles. The battery prefers a partial rather than a full discharge. Frequent full discharges should be avoided when possible. Instead, charge the thinkpad x61 tablet battery more often or use a larger battery. There is no concern of memory when applying unscheduled charges.

Although lithium-ion is memory-free in terms of performance deterioration, batteries with fuel gauges exhibit what engineers refer to as “digital memory”. Here is the reason: Short discharges with subsequent recharges do not provide the periodic calibration needed to synchronize the fuel gauge with the battery’s state-of-charge. A deliberate full discharge and recharge every 30 charges corrects this problem. Letting the thinkpad x61s battery run down to the cut-off point in the equipment will do this. If ignored, the fuel gauge will become increasingly less accurate. (Read more in ‘Choosing the right battery for portable computing’, Part Two.)

Aging of lithium-ion is an issue that is often ignored. A lithium-ion battery in use typically lasts between 2-3 years. The capacity loss manifests itself in increased internal resistance caused by oxidation. Eventually, the cell resistance reaches a point where the pack can no longer deliver the stored energy although the battery may still have ample charge. For this reason, an aged battery can be kept longer in applications that draw low current as opposed to a function that demands heavy loads. Increasing internal resistance with cycle life and age is typical for cobalt-based lithium-ion, a system that is used for cell phones, cameras and laptops because of high energy density. The lower energy dense manganese-based lithium-ion, also known as spinel, maintains the internal resistance through its life but loses capacity due to chemical decompositions. Spinel is primarily used for power tools.

The speed by which lithium-ion ages is governed by temperature and state-of-charge. Figure 1 illustrates the capacity loss as a function of these two parameters.

Figure 1: Permanent capacity loss of lithium-ion as a function of temperature and charge level.
High charge levels and elevated temperatures hasten permanent capacity loss. Improvements in chemistry have increased the storage performance of lithium-ion batteries(lenovo battery).

The mentioning of limited service life on lithium-ion has caused concern in the battery industry and I will need to add some clarifications. Let me explain:

If someone asks how long we humans live, we would soon find out that the longevity varies according to life style and living conditions that exist in different countries. Similar conditions exist with the batteries(thinkpad x40 battery,thinkpad x41 battery), lithium-ion in particular. Since BatteryUniversity bases its information on the feedback from users as opposed to scientific information derived from a research lab, longevity results may differ from manufacturer’ specifications. Let’s briefly look at the various living conditions of the lithium-ion battery.

The worst condition is keeping a fully charged battery at elevated temperatures, which is the case with running laptop batteries. If used on main power, the battery inside a laptop will only last for 12-18 months. I must hasten to explain that the pack does not die suddenly but begins with reduced run-times.

The voltage level to which the cells are charged also plays an important role to longevity. For safety reasons, most lithium-ion cannot exceed 4.20 volts per cell. While a higher voltage boosts capacity, the disadvantage is lower cycle life. Figure 2 shows the cycle life as a function of charge voltage.

Figure 2: Effects on cycle life at different float charge levels (Choi et al., 2002)
Higher charge voltages boost capacity but lower cycle life.

There are no remedies to restore lithium-ion once worn out. A momentary improvement in performance is noticeable when heating up the battery. This lowers the internal resistance momentarily but the condition reverts back to its former state when the temperature drops. Cold temperature will increase the internal resistance.

If possible, store the battery in a cool place at about a 40% state-of-charge. Some reserve charge is needed to keep the thinkpad t40 battery and its protection circuit operational during prolonged storage. Avoid keeping the battery at full charge and high temperature. This is the case when placing a cell phone or spare battery in a hot car. Running a laptop computer on the mains has a similar temperature problem. While the battery is kept fully charged, the inside temperature during operation rises to 45°C (113°F).

Removing the thinkpad t41 battery from the laptop when running on fixed power protects the battery from heat. With the concern of the battery overheating and causing fire, a spokesperson for the U.S. Consumer Product Safety Commission advises to eject the battery of affected laptops and to run the machines on a power cord. It should be noted that on a power outage, unsaved works will be lost.

The question is often asked, should the laptop be disconnected from the main when not in use? Under normal circumstances, it should not matter with lithium-ion. Once the battery is fully charged, no further charge is applied. However, there is always the concern is malfunction of the AC adapter, the laptop or the thinkpad t42 battery.

A large number of lithium-ion batteries for cell phones are being discarded under the warranty return policy. Some failed batteries are sent to service centers or the manufacturer, where they are refurbished. Studies show that 80%-90% of the returned batteries can be repaired and returned to service.

Some lithium-ion batteries fail due to excessive low discharge. If discharged below 2.5 volts per cell, the internal safety circuit opens and the battery appears dead. A charge with the original charger is no longer possible. Some battery analyzers (Cadex) feature a boost function that reactivates the protection circuit of a failed battery and enables a recharge. However, if the cell voltage has fallen below 1.5V/cell and has remained in that state for a few months, a recharge should be avoided because of safety concerns. To prevent failure, never store the battery fully discharged. Apply some charge before storage, and then charge fully before use.

All personal computers (and some other electronic devices) contain a battery for memory back up. This thinkpad t43 battery is commonly a small non-rechargeable lithium cell, which provides a small current when the device is turned off. The PC uses the battery to retain certain information when the power is off. These are the BIOS settings, current date and time, as well as resource assignment for Plug and Play systems. Storage does shorten the service life of the backup battery to a few years. Some say 1-2 years. By keeping the computer connected to the main, albeit turned off, a battery on the PC motherboards should be good for 5-7 years. A PC should give the advanced warning when battery gets low. A dead back-up battery will wipe out the volatile memory and erase certain settings. After thinkpad r50 battery is replaced, the PC should again be operational.

Longevity of high-power lithium-ion

Generally speaking, batteries live longer if treated in a gentle manner. High charge voltages, excessive charge rate and extreme load conditions will have a negative effect and shorten the thinkpad r52 battery life. This also applies to high current rate lithium-ion batteries.

Not only is it better to charge lithium-ion battery at a slower charge rate, high discharge rates also contribute the extra wear and tear. Figure 3 shows the cycle life as a function of charge and discharge rates. Observe the good laboratory performance if the battery is charged and discharged at 1C. (A 0.5C charge and discharge would further improve this rating.)

Figure 3: Longevity of lithium-ion as a function of charge and discharge rates.

A moderate charge and discharge puts less stress on the thinkpad r40 battery, resulting in a longer cycle life.

Battery experts agree that the life of lithium-ion depends on other factors than charge and discharge rates. Even though incremental improvements can be achieved with careful use of the battery, our environment and the services required are not always conducive to achieve optimal battery life. The longevity of a battery is often a direct result of the environmental stresses applied.

Avoid frequent full discharges because this puts additional strain on the thinkpad t40 battery. Several partial discharges with frequent recharges are better for lithium-ion than one deep one. Recharging a partially charged lithium-ion does not cause harm because there is no memory. (In this respect, lithium-ion differs from nickel-based batteries.) Short battery life in a laptop is mainly cause by heat rather than charge / discharge patterns.

Batteries with fuel gauge (laptops) should be calibrated by applying a deliberate full discharge once every 30 charges. Running the pack down in the equipment does this. If ignored, the fuel gauge will become increasingly less accurate and in some cases cut off the device prematurely.

Keep the lithium-ion battery cool. Avoid a hot car. For prolonged storage, keep the battery at a 40% charge level.

Consider removing the battery from a laptop when running on fixed power. (Some laptop manufacturers are concerned about dust and moisture accumulating inside the battery casing.)

Avoid purchasing spare lithium-ion batteries for later use. Observe manufacturing dates. Do not buy old stock, even if sold at clearance prices.

If you have a spare lithium-ion battery, use one to the fullest and keep the other cool by placing it in the refrigerator. Do not freeze the battery. For best results, store the thinkpad t42 battery at 40% state-of-charge.

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How to calibrate the ’smart’ lenovo battery

November 24th, 2009

With use and time, a tracking error occurs between the chemical battery and the digital sensing circuit. This results in a loss of accuracy of the SoC readout.

The most ideal use of the ’smart’ thinkpad x61 tablet battery, as far as fuel-gauge accuracy is concerned, is a full charge followed by a full discharge at a constant current. In such a case, the tracking error would be less than 1% per cycle. In real life, however, a battery may be discharged for only a few minutes and the load may vary widely. Long storage also contributes to errors because the circuit cannot accurately compensate for self-discharge. Eventually, the true capacity of the battery no longer synchronizes with the fuel gauge and a full charge and discharge is needed to ‘re-learn’ or calibrate the battery.

What happens if the lenovo thinkpad x61 tablet battery is not calibrated regularly? Can such a battery be used in confidence? Most ’smart’ battery chargers obey the dictates of the chemical cells rather than the electronic circuit. In this case, the battery will fully charge regardless of the fuel gauge setting and function normally, but the digital readout will become inaccurate. If not corrected, the fuel gauge simply becomes a nuisance.

If no full discharge occurs for a few months as part of normal operation, a deliberate full discharge is needed. This can be done on the equipment itself, on a charger with discharge function or with a thinkpad x60 tablet battery analyzer. Cadex manufactures SMBus chargers and battery analyzers, both of which can be used to test and calibrate the battery. The Cadex SM2+ (Figure 4) is a level-3 SMBus charger featuring a target capacity selector that is adjustable to 60%, 70% or 80%. The target capacity selector checks performance and flags batteries that do not meet the set requirements.lenovo 40Y6795 ,40Y6797,40Y6799.

If a battery falls below target, the charger triggers the condition light. The user is prompted to press the condition button to calibrate and condition the battery by applying a charge/discharge/charge cycle. The green ‘ready’ light illuminates if the capacity is met at full charge. If the battery does not recover, a fail light recommends replacement. The SM2+ charger accommodates batteries with the 5-prong knife connector by AMP. The charger services both SMBus and non-SMBus batteries. “Dumb’ batteries do not provide state-of-health indications.

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