440 Volt battery. Frequently asked questions about Batteries

Battery 45Wh original suitable for HP ProBook 440 G7

We keep receiving inquiries regarding several performance data in mAh on the supplied batteries. Which performance value is relevant for the notebook owner for the runtime in battery mode?

Why are notebook batteries often a few years old when you buy them?

If original notebook batteries are available, we also use them for repairs. But very often we get a question from customers who take a closer look at the label on the battery, why the notebook battery is so old.

How can I recharge my notebook battery to 100%?

Whether old or new, often used or dust catchers, notebook batteries are prone to defects. It is therefore important to take various measures to maximize capacity and service life.

  • If you mainly use your laptop while it’s connected to mains, you should remove your battery and only charge it every one to two months.
  • Don’t fully discharge your battery, because this can lead to a depth discharge. Charge the battery again, when between five and seven percent of charge remain.
  • If possible charge your battery while the notebook is turned off. The optimal temperature for batteries is between 10 and 30°C, this range is usually exceeded in a powered-on notebook.
  • If you have multiple batteries for your device, rotate between them.
  • After being uncharged for a while, the battery needs about two to three complete charge cycles to reach its full capacity again.
  • Avoid high temperatures for example due to direct sunlight or being left in a hot car. High temperatures increase the self-discharging rate.
  • Rechargeable Lithium-Ion batteries, which are found in nearly all modern electronics, have a limit of somewhere between 500 to 1000 charge cycles. However, turning your laptop on and off while plugged in is one charge cycle. This is why we recommend removing the battery when using the device plugged in for a longer time.
  • Furthermore, it would be optimal to never fully charge or discharge your battery, but rather to keep it between 20% 80% charge.

Some manufacturers integrate a battery protection function in their notebooks. This function only allows charging up to 80% capacity to prolong he lifespan of the battery.

The so-called memory-effect of a Lithium-Ion battery can be disregarded in normal use, a complete charge after a complete discharge is not needed.

On the contrary for many modern devices the opposite is true, it is best to keep the charge between 20% and 80%. This is due to the sensitivity of Lithium-Ion batteries to depth discharge and overcharge. However, in most devices control electronics prevent the user from making any grave mistakes. For example, Apple implements a function which charges the battery as fast as possible up to 80% but charging slows down a lot after that. This conserves the lifespan of the battery at the cost of charge time.

One thing that should be avoided though is leaving your device plugged in for many days in a row. The battery should be discharged once in a while to move the ions inside.

  • Use the energy saving function in Windows found in the system controls und the power options
  • Reduce the brightness of your screen since it consumes most of the power in a laptop.
  • Turn off Wi-Fi or Bluetooth when it is not needed.
  • Disconnect external devices like hard drives when not in use.
  • Deactivated unnecessary tools or programs, that are running in the background.
  • The battery should be completely charged before usage.
  • Afterwards drain it down to 10% charge and fully charge it again.
  • Now it is ready for use.

Rechargeable Lithium-Ion batteries are the most commonly used energy storage and offer a high energy density.

The CE certification mark, confirms that the battery is compliant with all guidelines of the European Union.

The RoHS mark confirms, that the battery complies with the EU-regulations for the restriction of the usage of certain dangerous materials in electronic devices.

The REACh certification mark confirms, that the chemicals used conform to EU regulations.

If the WEEE-Logo is on the battery the cost for the proper disposal of it has already been paid for by IPC-Computer

If the Li-Ion Recycling-Logo is on the battery the cost for the proper disposal of it has already been paid for by IPC-Computer

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The safety test according to UN38.3 has been passed. The battery is safe for transport aboard a plane.

  • Design capacity: This value specifies the maximum of energy that can be stored in the battery. This value is used for statements on the runtime of the device.
  • Rated capacity: specifies the theoretical capacity of the battery according to IEC norm 61951. Afterwards charge still remains in the battery.
  • CE-capacity: complies with EU regulation 765/2008, usually the rated capacity.

Brand-new Lenovo ThinkPad S3-S440 Battery Replacement

High Quality Components This Lenovo ThinkPad S3-S440 battery replacement has built-in A grade cells and high-quality TI intelligent control chip, which not only performs better, charges faster but lasts longer. In addition, the outer shell of the Lenovo ThinkPad S3-S440 battery is made according to the original battery shape design scheme, using high temperature and wear-resistant ABS PC alloy environmentally friendly materials, which can be 100% compatible with your laptop and fit closely.

100% True Capacity Do not be deceived by the false capacity advertisements from bad merchants, of which battery capacity will often drop off significantly after using a few months. Made with the highest quality A grade cells, our Lenovo ThinkPad S3-S440 laptop battery has passed various strict quality tests to ensure that it meets OEM specifications, which can provide more than 600 charging cycles to maintain the same capacity for a long time.

Safety Is Vital! Using a poor battery with unstable performance may do harm to the notebook and your safety. Our Lenovo ThinkPad S3-S440 replacement battery has passed CE, UL, ROHS, and other international authority certifications, which provides a variety of protection functions, effectively preventing common risks such as short circuits, overheating, and overvoltage. In order to protect your laptop and your safety, please rest assured to purchase our high-quality batteries!

Service is better than promised

Secure Packaging To ensure that the new Lenovo ThinkPad S3-S440 battery can be safely delivered to your hands, it will be firstly packed in an anti-static bag, then wrapped with a drop-proof synthetic foam, finally enclosed into sturdy cardboard and sealed with waterproof plastic tape.

Fast Shipping The shipment will be arranged within 24 hours (working day) after we receiving the order. The shipping notification will be sent via email after confirming the shipment, which will contain the details of your order and tracking information of the package.

30 Days Money Back In order to minimize the risk during the purchase process from customers, our return period is 30 days instead of 7 or 14 days! You can easily request a refund within 30 days since receiving the product if you are not satisfied with our Lenovo ThinkPad S3-S440 laptop battery or our service.

Free Repair/Replacement Do not worry about the Lenovo ThinkPad S3-S440 replacement battery which is purchased from us will not be performed well after a few months. Having been focused on Lenovo laptop batteries for more than 10 years, it is rarely failed with our batteries. If the battery you purchased has a faulty performance that is not artificially damaged within one year, not only free repair services and even a new replacement we are willing to provide, but also the shipping cost will be borne by us.

  • Overvoltage Protection
  • Overcharge Protection
  • Over Discharge Protection
  • Electromagnetic Protection
  • Overheating Protection
  • Short Circuit Protection
  • ESD Protection
  • Charging Time Protection
  • Overcurrent Protection
  • Power Protection
  • Intelligent Protection
  • Class A Protection

The Lenovo ThinkPad S3-S440 battery compatibility list is incomplete. If you are not sure whether it is suitable for your Lenovo laptop, please leave the model of your Lenovo laptop through Support for Product Search, and we will quickly choose the right battery for you.

Compatible Battery Part Numbers

  • 121500158
  • 45N1141
  • 45N1138
  • 121500159
  • 45N1140
  • 45N1139

Compatible Laptop Models

  • ThinkPad S3-S440
  • ThinkPad S440 TOUCH(20AY001DGE)
  • ThinkPad S440
  • ThinkPad S440 TOUCH
  • ThinkPad S440 TOUCH(20AY001DMZ)
  • ThinkPad S440-20AY
  • ThinkPad S431
  • ThinkPad S440 TOUCH(20AY0050AT)
  • ThinkPad S440 TOUCH(20AY006EGE)
  • ThinkPad S431-20BA
  • ThinkPad S431-20AX

Disclaimer: LenovoBatt.com only sells high-quality replacement batteries instead of original batteries. We mention the original manufacturer’s brand and model only to illustrate the compatibility of the battery type, so that customers can correctly purchase replacement batteries suitable for Lenovo ThinkPad S3-S440.

How can I check if the Lenovo ThinkPad S3-S440 battery is compatible with my laptop?

First, find out your old battery part number, or the laptop model name, and then match it with the Compatibility List above. Secondly, please compare the old batteries with our product pictures to ensure that they have the same interface and shape. Finally, check whether the voltage of this battery is the same as the old battery. If you are still unsure whether it is suitable for your laptop, you can note the laptop model when placing an order, so that we can confirm that you have purchased the correct battery. Or leave your laptop model via Support for Product Search and we will select the appropriate battery for you.

  • Cell Type: Generally speaking, Li-ion and Li-Polymer batteries are the best choices. Compared with NiMH batteries in the past, they have a longer life, faster charging, more environmental protection, and one-third lighter weight.
  • Voltage: Please note that there may be two or more different voltages, such as 11.1 V and 14.8V, matching the same laptop model. They are completely incompatible with each other.
  • Capacity: A higher capacity battery can power your laptop longer. At the same time, high capacity batteries are much larger in size, weight, and higher in price. You can make a choice based on your needs.
  • Condition: Be sure to choose Brand New. You have no good reason to buy a refurbished battery (or an unused battery covered dust somewhere on the shelf). Check the production date. Batteries have been in production for more than 2 years should be denied.

If Tools come with after buying the Lenovo ThinkPad S3-S440 battery?

If you purchased a built-in battery (located inside the laptop), we will send the complete installation tools for free. If you purchase a removable battery located on the outside of the laptop (slide the battery latch to remove it), there are no tools included. Although a few batteries are located on the outside of the laptop fixed by screws, and we will also give away disassemble tools.

No need. Our laptop batteries are all lithium-ion batteries, not nickel-cadmium! They do not have any memory effect, just higher capacity and more environmentally friendly design. But they are low-power-sensitive. It is huge damage to lithium-ion batteries to completely exhaust the power and even damage the battery immediately.


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Reader Interactions

Dave, When you have two batteries say 1- 80ah and 1-70ah would that mean a total of 150 ah and half of that is usable (75ah) before being hard on the batteries? Or does it effect the first/last battery differently than the other one? Thanks for all the help you’ve offered along the way.

It is not a good idea to have dissimilar battery pairs eg 80 amp/hr and 70 amp/hr You will only have 140 amp/hrs as the higher amp/hr battery only charges to the lower

  • Dave Helgeson. Adventures in RVing says November 16, 2019 at 1:02 pm
volt, battery, questions, batteries

Hersh, For starters if the batteries are wired together in parallel ALWAYS use like batteries. Now to answer you question – yes you would have 150 total amp hours capacity, but only 75 amp hours usable (50% of rated capacity). If the batteries are alike and wired together parallel correctly they would draw down evenly under load. If you must use dislike batteries you should keep them isolated and draw them down separately.

Dave, Oops! Just backwards. To determine useful time divide battery Ah capacity (actually 1/2 battery capacity) by Ah usage. If usage is 20 Ah per day and battery capacity is 80 Ah you can go two days without significant battery damage. That is, 40 Ah capacity (1/2 rated battery capacity) divided by 20 Ah per day.

Dave Helgeson. Adventures in RVing says November 16, 2019 at 1:12 pm

Wilyoung, Thanks for the comment – I could have worded it a bit better. “divide that number into the amp hours available” AH capacity / amp hour load = hours

A disconnect switch is not necessary, but is convenient for keeping your batteries from parasitic loads (gas detector, clock radio, etc) while in storage.

Amp hr ratings on batteries are close to true when brand new. After use it lowers and not equally for each battery. Batteries need to be well maintained and kept full of distilled water. As far as batteries I have found with experience of of about 20 yrs of using power inverters that the only battery I would buy is Trojan batteries. After using many brands and capacity I for the last 8 years would buy the highest rating amp hr they sold. They are expensive but worth the money. I found a site where I could buy them at Hodkins in Tucson,AZ and pick them up at any Trojan dealer will call and pre-paid. These batteries would perform more than 2 times better. Even over the well over states Interstate batteries. As far as amp hr or amp ratings of devices what is posted on device is maximum and not operational. Operational is usually a lot lower than the rating. Sometimes motors like AC units have may even be higher than ratings when older. That is why putting a real high rated and well maintained battery pack will serve you well.

volt, battery, questions, batteries

Someone told me that two 6 volt batteries in series is better than two 12 volt batteries in parallel. The Ah becomes higher. Is this true? I need to replace my two batteries and wonder if two 6 volts is the way to go. A little more expensive. Thanks.

Not if the amp/hrs are equivalent on the 6 and 12 volt batteries When you add the 6 volt batteries together to make 12 the amp/hrs stay the same where as the 2 12 volt batteries amp/hrs would double in a 12 volt system

I’m going to the trip soon but I scare that my RV batteries not as good as befor. The information is very useful for me. Thanks so much!

I had no idea that deep-cycle batteries are measured in amp-hours. I look forward to getting an RV before Christmas so I can go on a big road trip with my family. I’ll look into getting a deep-cycle battery that is amp-hours instead of watt-hours.

So if I have 1 80ah battery and I am using 20 amps a day it would last 2 days? How many watts solar suit case would I need to keep the battery charged ?

Dave, good article that covers the basics. Our trailer came with two new RV deep cycle batteries and I soon learned that I never got the expected life from them (or I should say half life as I didn’t want to drain them beyond 50%). I eventually found that the WFCO converter in the trailer did not fully charge them to 100%. I installed a Renogy DC-DC charger and they now charge to 100%. Deep cycle and AGM batteries need higher voltage than a wet cell (Maintenance Free) battery used in most vehicles.

I’m looking at a 12v fridge that has a rating of 340w/24 hours. I’m confused on how to get an amp hour rating. Help!

That is completely wrong. Watts per hour is meaningless. You have probably read the specifications wrong. It is probably 340wh per 24 hours would mean something useful. That would give 340wh / 12v = 2.8 ah per day. If your appliance actually uses 340w while running continuously for 24 hours, then 340w 24 hours / 12v = 680Ah / day which would be very bad. The appliance actually runs only a fraction of the time, this fraction is called the “duty cycle”. You must know or estimate this to calculate useful numbers. If the duty cycle is %10 then you would be down to 68Ah / day, if the duty cycle is %1 then you would be at 6.8Ah / day. Appliances are generally not rated in terms of watt-hours or amp-hours because it would depend on how long they were running. They are rated in watts or amps while running.

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