Tag Archives: Li-Ion

Power Management Solutions: Battery Chargers


Maurizio @ dev.emcelettronica.com writes:

Out of all portable devices, the most numerous are the mobile phones (Figure 1). Most of them feature Li-ion or Li-polymer accumulators and Freescale has a broad range of charger ICs dedicated to supporting all the phases of a complete recharge cycle. Generally speaking the charging of a mobile phone is performed by taking energy from:

a) from a wall outlet
b) from the USB port of a computer
c) from the 12V output of a vehicle

Power Management Solutions: Battery Chargers – [Link]

IC monitors multicell battery packs

Intersil ISL94203

by Susan Nordyk @ edn.com:

The ISL94203 battery-pack monitor IC from Intersil monitors, protects, and cell-balances three- to eight-cell rechargeable battery packs, supporting Li-ion CoO2, Li-ion Mn2O4, and Li-ion FePO4 chemistries. Its internal state machine has five preprogrammed stages that accurately control each cell of a battery pack to extend operating life.

In addition to functioning as a stand-alone battery-management system for rechargeable Li-ion battery packs, the ISL94203 can be used with an external microcontroller communicating via an I2C interface. The device integrates high-side charge/discharge FET-drive circuitry, which allows the battery pack to be securely ground referenced.

IC monitors multicell battery packs – [Link]

Get a constant +5V output by switching between a +5V input and a single-cell LI+ rechargeable cell


App note from Maxim Integrated on providing smooth power from two sources. Link here (PDF)

Design provides a simple method for maintaining an uninterrupted +5V even while switching between the external +5V supply and a rechargeable single-cell Li+ battery.

Get a constant +5V output by switching between a +5V input and a single-cell LI+ rechargeable cell – [Link]

Buck battery charger handles multiple chemistries


by Susan Nordyk @ edn.com:

The LTC4015 synchronous step-down battery charger controller from Linear Technology offers charge current of up to 20 A, multiple-chemistry operation, and onboard digital telemetry. The controller transfers power from a variety of input sources, such as wall adapters and solar panels, to a Li-Ion polymer, LiFePO4, or lead-acid battery stack with system load up to 35 V.

Operating over an input voltage range of 4.5 V to 35 V, the LTC4015 provides ±5% charge-current regulation up to 20 A and ±0.5% charge-voltage regulation. While a host microcontroller is required to access the most advanced features of the LTC4015, the use of an I2C port is optional.

Buck battery charger handles multiple chemistries – [Link]

How to make a USB Li-Ion charger


by Robert Gawron @ robertgawron.blogspot.com:

Li-ion cells become more and more popular due to their capacity and reasonable prices. In this entry I will present how to build a simple li-ion battery charger based on MCP73831 chip. It’s a quite useful device for DYI projects,in addition its cost is only around 1,5 euro.

The device uses USB port as a power supply (mini-USB connector). I use the standard gold-pins as an output socket. There’re three of them, but only two are used (looking on the image, counting from top: V+, V-). I will design my li-ion based devices in the same way (same socket, but female), then if I will connect it in the incorrect direction (rotated 180 degrees) they won’t be damaged (V- connected to V-, but V+ connected to n/c pin) – simple way to avoid plugging in an incorrect way.

How to make a USB Li-Ion charger – [Link]

Research Points the way to Safer Lithium Batteries


by Martin Cooke @ elektormagazine.com:

A paper published in the June 17th edition of Nature Communications describes how the addition of two chemicals to the electrolyte of lithium metal batteries can prevent the formation of dendrites. These are needles of lithium which grow in the battery and eventually puncture the barrier between the two battery halves. Their formation can cause short circuits in the battery which leads to overheating and sometimes combustion.

According to the paper this breakthrough could help remove a major barrier to the future development of lithium-sulfur and lithium-air batteries. These promising new battery technologies could store up to 10 times more energy per weight than batteries in use today in consumer electronics and electric cars.

Research Points the way to Safer Lithium Batteries – [Link]

Samsung Researchers Nearly Double Lithium-ion Battery Capacity


by GardenState @ element14.com:

Silicon is receiving considerable attention as an active material for next- generation lithium-ion battery anodes because of its gravimetric capacity–a measure in mAh/g of the total charge capacity stored by the cell or battery, per gram of the battery’s weight.

Unfortunately, the large volume change of silicon during charge–discharge cycles has in the past weakened its competitiveness. Recently, however, a research group from Samsung reported in the publication Nature Communications that using direct graphene growth over silicon nanoparticles without silicon carbide formation resulted in a near doubling of run-time by expanding energy density– the amount of stored power in a given area — to 1.8 times that of current batteries.

Samsung Researchers Nearly Double Lithium-ion Battery Capacity – [Link]

IC manages battery-backup systems


Housed in a low-profile 24-pin QFN package, the LTC4040 from Linear Technology is a 2.5-A lithium-battery–backup power-management system for 3.5-V to 5-V supply rails that must be kept active during a main power failure. The device uses an on-chip bidirectional synchronous converter to provide high-efficiency battery charging, as well as high-current, high-efficiency backup power.

When external power is available, the LTC4040 operates as a step-down battery charger for single-cell lithium ion or lithium iron phosphate batteries, while giving preference to the system load. When the input supply drops below the adjustable power-fail-input threshold, the LTC4040 operates as a step-up regulator capable of delivering up to 2.5 A to the system output from the backup battery. In the event of a power failure, the part provides reverse blocking and a seamless switchover between input power and backup power.

IC manages battery-backup systems – [Link]