About the article

LiPo Auto Balancer

Automatic balancing for LiPo battery packs

LiPo Auto Balancer
LiPos are becoming the cell of choice for a growing range of mobile applications. What exactly are 2s, 3s and 4s battery packs and why do they need balancing anyway? In this article we will shed some light on the subject.
Downloading of this magazine article is reserved for Elektor Members only.
Already a member? click here to log in.
Products
Gerber file

CAM/CAD data for the PCB referred to in this article is available as a Gerber file. Elektor Members can exclusively download these files for free as part of their Membership. Gerber files allow a PCB to be produced on an appropriate device available locally, or through an online PCB manufacturing service. Elektor recommends its business partner Eurocircuits as the company of choice for its own prototypes and volume production in selected cases.

Extra info, Update
• Fully automatic balancing
• Two LED indicators per cell
• Voltage range 6 to 32 V (6 to 44 V using an LM348n)
• Selectable LiPo pack size from 2s to 5s using jumpers
• Lead-acid cells from 3s to 5s can be balanced
• Balance can be performed on two LiPo packs (up to 5s each)
• 200 mA balancing current (expandable)
• Balancing of cells with 2 Ah to 10 Ah capacity (expandable)
• 2.5 mA quiescent current with 5s and 1 mA with 2s packs
Resistors
R1–R5 = 10kOhm 0.1%
R6–R9 = 1.5kOhm
R10–R13 = 1.2Ohm
R14–R17 = 1Ohm
R18 = 8.2kOhm
Capacitors
C1–C4 = 10nF, lead pitch 5mm
C5,C6 = 100nF lead pitch 5mm
Semiconductors
D1–D4 = LED, green, low current, 5mm
D5–D8 = LED, yellow, low current, 5mm
D9 = LED, read, low current, 5mm
D10–D17 = 1N4148
T1–T4 = TIP120
T5–T8 = TIP125
IC1 = LM324, LM348N (see text)
Miscellaneous
K1 = 6-pin SIL pinheader, lead pitch 0.1 in. (2.54mm)
JP2-1–JP4-2 = 4-pin double row pinheader, lead pitch 0.1 in. (2.54mm)
JP5 = 2-pin pinheader, lead pitch 0.1 in. (2.54mm)
14-way IC socket for IC1
10 pcs heatsink isolation set for TO220 style transistor
Aluminium bracket or heatsink
PCB # 090476
Loading comments...