the "little Makita battery and device-HowTo"

###### Charger DC18RC ######
The charger is probably the price / performance ratio the best of all well-known cordless tool manufacturer.
There is in my opinion only a small negative point and that is the volume of the fan. However, to me, a loud fan (high cooling capacity) is rather I get this for extremely short charging times.

Excerpt from the manual (as of 07.2014)
The Ladegrät is suitable for the following Makita batteries:
Ni-MH batteries 9.6V 12V 14.4V ...
Li-ion batteries 14.4V, 18V

Type: ............ Capacity in Ah ....... charging time in minutes "my info"
BL1415 ........................... 1.3 ................... ................ 15 Makita-Star Healthy -?
BL1415NA ..................... ......................... 1.5 ........... 15 Makita-Star Healthy -?
BL1430 / A 3 ......................... ..................... ............... 22 Makita-Star Healthy -?
BL1440 ... * 1 ...................... ..................... 4 ............... 36 Makita-Star Healthy -?
BL1815 ........................... 1.3 ................... ................. 15 Makita-Star Healthy - NO
BL1815N ....................... ....................... 1.5 ............. 15 Makita-Star Healthy - YES
BL1820 ... * 1 .................... 2 ....................... ................ 18 -> NEW not available?
BL1830 ............................. 3 ................... ................. 22 Makita-Star Healthy - YES (current)
BL1840 ... * 1 ........................ ................... 4 ................. 36 Makita-Star Healthy - YES
BL1850 ... * 1 ........................ ................... 5 ................. 45 -> NEW not available?

* 1 These batteries can be charged only with the DC18RC (not with DC18RA)

Link to manual:
[...]
###### End charger ######

###### IMPORTANT -> Makita-Star Technology ######
The Makita-Star technology is required for the use of the new / current high-performance batteries. The batteries must have a "Star (Star)" stamped in the housing. The devices must have a yellow base, yellow base with star or black socks with star.
###### End Makita-Star ######

###### 36V devices with adapters or directly with 2x18V batteries usable ######
Makita increasingly becoming 36V devices can be powered by batteries 2x18V. Thus one has practically units with power ranging from "700Watt cable equipment" and more (my estimate based on various data sheets).
With the current 2x18V you then towards the widespread 36V 2,6Ah batteries great price and endurance benefits (Wh).

Wh / corresponds to the stored energy that is available to the "Work carried out". This is calculated with "capacity times voltage" or "Ah * V = Wh". This gives the following values:

BL1850 - 2x90Wh = 180Wh (coming soon)
BL1840 - 2x72Wh = 144Wh
BL1830 - 2x54Wh = 108Wh
BL1815N - 2x27Wh = 54Wh

contrast 36V battery (prices around 200, - or more)
BL3626 - 36V 2,6Ah * = 93,6Wh

All brands approve at the 36V battery a hefty price premium to 18V batteries. Two 18V batteries and 18V chargers 2 cost in extreme cases, only 50% of the 36V versions, with the same Wh value.

For garden equipment and larger tools are required to 36V a power ranging from 240V / cable devices ensure. Here 4 x BL1830 + 2 Chargers for the operation of all 18V and 36V devices for workshop, building and garden are then absolutely unbeatable price / performance ratio. This professional equipment are realistic for the price of good Hobby / DIY equipment.
###### End 36V ######

#### Current (07.2014) developments and availability: ####

The current 18V cordless range now includes:
BL1840 - 4Ah
BL1830 - 3Ah
BL1815N - 1.5Ah
(Old BL1815 - 1.3Ah no Makita-Star Technology)

First device descriptions of Makita surfaced with the new
BL1850 - 5Ah (not yet available in Germany ?!). Likewise, there is evidence of a slight BL1820 - 2Ah.

All the devices were renamed BXX DXX to document compatibility with the BL1840 battery.
However, all seem (? There are exceptions? Please comment as goes here) device with the Makita-Star technology to be compatible with the BL1840 and BL1850 coming.

#### Review of 2013: ####

All cordless tools with an asterisk (Makita-Star Technology) in addition to the battery contacts, this means the loss of critical surveillance. The current Makita battery BL1830, BL1840 and BL1815N (N! 1.5Ah) have a built-in logic that allows an extension of the service life and higher power demands.

see: "makitatools.com/en-us/Modules/Tools/LXTAdvantage/StarProtection.aspx"

I have bought in the past few months many Makita cordless tools. From various sources (Amazon, retailers and eBay). For all tools with 18V batteries work instead of the intended BL1830 also much lighter BL1815N. Only in 36V adapter (2x18V BL1830 series) for chainsaw BUC250 and hedge trimmer of BL1815N does not according to the catalog. In practice, however wonderful and the relatively large device makes super-easy.

I use practically all devices every now and then the light BL1815N. Especially if I want to have the lightest possible tool. This is such. As the hammer drill as wood chisels, the impact wrench in an unfavorable position or the Circular Saw with very fine and precise cuts.

Are of the BL1830 / were? it here at Amazon two variants. An older and a newer lt. Amazon info text. I ordered the newer version and get a BL1830 with Makita-Star. The older BL1815 (1.3Ah) fit mechanically into the machine, the newer BL1815N Makita-Star machines, however, can in all (? With me already) be used.