# Lithium ion battery cutoff current?

For an upcoming ESP8266 project, I need to use a relatively large (or several smaller) batteries and am hoping to get at least 10Ah. To achieve long life, I will be utilizing one of the ESP8266's available sleep modes. In the deep sleep mode, it utilizes somewhere between 10 and 70 microamps.

I know that most lithium ion batteries are recommended to discontinue discharge at a voltage of around 3.0-3.2V, for the sake of battery health. However, do they also have any kind of limitation such that the battery will not supply current if the load goes below, say, 1mA? I apologize if this is a nonsensical question, but I know very little about batteries, and I want to ensure I can put it into deep sleep while using a battery like this.

• Batteries themselves have no cutoff values, managing circuitry around them has. – PlasmaHH Aug 4 '16 at 17:32
• Please edit your question its a little confusing, you can draw a battery to near zero volts if you continue drawing current out of it. Which will kill the battery – Voltage Spike Aug 4 '16 at 17:58
• Lithium, lithium ion (Li+) and lithium polymer (LiPo) batteries all have different characteristics. It looks like you mean lithium ion. – jbarlow Aug 4 '16 at 21:19
• @laptop2d, edited to be more clear – Josh Aug 4 '16 at 22:20
• @jbarlow, edited to be more clear – Josh Aug 4 '16 at 22:22

In terms of the physics, the minimum current you can have is the resistance of the air between the two external terminals in parallel with any internal leakage. The resistivity of an air gap is ~$10^{16}$ Ω·m which will also works to out a resistance of ~$10^{16}$ Ω between two terminals on a battery, or about 0.4 fA (femtoamperes) at 4 V.