====== General ======

  * PCM -- Protection Circuit Module
  * SU -- Safety Unit
  * BMS -- Battery Management System
  * Battery gauge -- Monitors battery health, capacity, percentage etc
====== Resellers ======
[[https://www.jauch.com/|Jauch]]

[[https://www.varta-microbattery.com/en/|Varta]]

[[https://actec.dk/|Actec]]

[[https://www.awilco.dk/batteries|Awilco]]

[[https://celltech.se/|Celltech]]





====== Certification ======
[[http://www.farnell.com/datasheets/2585501.pdf|Farnell's guide to batteries]] Also good info about certification.

  * Transport -- UN38.3
  * CE -- EN 62133-2
  * UL -- UL1642 (single cell), UL2054 (pack)

[[https://elsmar.com/elsmarqualityforum/threads/when-is-en-62133-1-new-version-i-e-iec-62133-2017-mandatory-in-eu.79117/#post-661059|Elsmar forum post]]


====== Lithium-ion ======
[[http://www.farnell.com/datasheets/2585501.pdf|Farnell's guide to batteries]] Also good info about certification.

<WRAP group>
<WRAP half column>
  * Lithium ions move from the negative elecrode to the positive electrode during discharge.
  * No memory effect
  * Flammable electrolyte
  * 3.0 V - 4.2 V / cell (except for some electrodes)


</WRAP>

| Specific energy | 100-265 Wh / kg    |
| Energy density  | 250-693 Wh / litre |
| Specific power  | 250-340 W / kg     |

<WRAP half column>
</WRAP>
</WRAP>

There are several Lithium ion batteries. The ones with a polymer electrolyte (instead of a liquid) are called Lithium polymer batteries.

| Short name | Positive electronde, cathode during discharge              || Negative electronde, anode during discharge || Nominal cell voltage |
| LCO | Lithium cobalt oxide        | <chem>LiCoO2</chem>             | Carbon/graphite || 3.6 V |
| LFP | Lithium iron phosphate      | <chem>LiFePO4</chem>            | Carbon/graphite || 3.2 V |
| LMO | Lithium ion manganese oxide | <chem>LiMn2O4</chem> or <chem>Li2MnO3</chem> | Carbon/graphite || 3.7 (3.8) V|
| NMC<sup>1</sup> | Lithium nickel manganese cobalt oxide | <chem>LiNiMnCoO2</chem> | Carbon/graphite || |
| NCA | Lithium nickel cobalt aluminium oxide | <chem>LiNiCoAlO2</chem> | Carbon/graphite || 3.6 V |
| LTO |  | <chem>LiMn2O4</chem> or <chem>LiNiMnCoO2</chem> |Lithium titanate            | <chem>Li4Ti5O12</chem> | 2.4 V |

<sup>1</sup> Also NCM, CMN, CNM, MNC, MCN depending on metal combinations

{{ ::battery-chemistry.png?direct&600 |}}

[[https://batteryuniversity.com/learn/article/types_of_lithium_ion|Battery university]]

===== Charging =====

  * Pre-conditioning -- Short-circuit test and trickle charge/pre charge
  * Thermal regulation -- Limits current to maintain temperature in the charger IC
  * Constant current -- Quick charge phase
  * Constant voltage -- Finish charging, stops completely after current threshold reached

All charging states are usually time limited, as a fault detection mechanism.

Charging a cell even 50mV higher than it's specified maximum voltage will drastically decrease the cycle life.

  * Low current or simple solution might allow for use of linear charger.
  * High current, or high efficiency, might require a switch-mode charger.

Power path (TI) allows system to work with a defective battery. It also allow the charger to monitor the charging current.

[[https://training.ti.com/introduction-li-ion-battery-charging?context=1139254-588|TI Training video]] -- Battery charging