Bosch, Dewalt, Makita, Milwaukee, Ryobi, Ridgid, Hilti battery specs

Intro

There is a handful of cordless power tool manufacturers out there, hundreds of various types of power tool batteries. Electric motors are the muscles that run power tools, and batteries are the heart of any tool. Battery plays a crucial role when it comes to power and runtime.

As a result of marketing wars and poor engineering, certain manufacturers go great lengths to conceal the specifications of their batteries, preventing consumers from making informed decisions when picking a power tool line.

I decided to dig up as much information as possible around the net, a lot from personal findings (opening up batteries), some from RC enthusiast forums, some from EV (el. vehicle) and EB forums. There is a great variety of cells with different capacity, voltage, maximum discharge current and cycle life.

So here’s my findings about cordless batteries. If you don’t like math and physics, the following text will most likely be a boring read for you. Otherwise, dive in!

What’s up with secret capacities?

Certain cordless power tool manufacturers keep battery capacities secret. Some do it to conceal the fact they use crappy cells, prevent customers from comparison-shopping or just to be able to stick “X % more runtime than previous model” on their new, only slightly better battery.

First of all, let me explain how battery capacity is measured. Capacity is measured in mA*h or A*h (milliamper-hours or amper-hours [you can also say amp-hours], also notated as Ah or mAh).

1 A*h = 1000 m*Ah. Notation can be in form of “mAh”, “m*Ah”, “A*h”, “Ah”, “mA-h”, “A-h”.

Basically, it shows how much current battery can supply for a period of time. Theoretically, 1 A*h battery can supply 1 ampere current for 1 hour, or 100 milliamperes for 10 hours, or 10 A for 1/10 of an hour or 6 minutes. There is a physical limit as to how much current can be produced, it depends on many parameters, mostly on battery’s chemical composition. So a battery rated 3 A*h will not necessarily be able to supply 30A for 6 minutes, or even 3 A for 1 hour. Even if it does, such load will most likely damage the battery.

What’s inside?

Batteries are made of series of cells, connected serially or parallel or combination of both.

When connected in parallel, the (+) terminals of all cells are connected to 1st common wire (aka bus or rail), and the (-) terminals are connected to the 2nd common wire. Voltage between common wires will not exceed voltage of an individual cell, but the capacity of such pack will be a sum of capacities of all cells in it.

When you connect cells serially, the (+) terminal of one cell is connected to the (-) terminal of the next cell, forming a “chain”. In such case voltage between the (+) of the first cell and (-) of the last cell will be a sum of voltages of all cells in the chain, but capacity of such chain will not exceed the capacity of one individual cell.

Example: 18 volt NiCd or NiMh batteries use 15 cells, 1.2 volts each, connected serially. 12 volt has 10 cells and so on.

Typical Li-Ion (aka Lithium-Ion) or Li-Po (aka Lithium Polymer) cell nominal voltage is 3.6 V. Cylindrical cells are also equipped with vents and PTC (positive temperature coefficient) devices that disconnect cells’ (+) or (-) terminal when they get too hot.

Li-Ion cell voltage goes up to 4.2 right after the charge, and should never go below 2.5 V. Some manufacturers use this in their marketing to present 10.8v tools as 12v tools. Milwaukee was the first and Bosch had to rebrand their tools from 10.8v to 12v. Bosch is more honest because they still provide a little diagram on the packaging explaining where 12v comes from with only three 3.6v cells in the battery.

If Li-Ion voltage drops below ~2.5 V, Li-Ion/LiPo cell will be damaged. Li-Ion/LiPo batteries have electronics inside that disconnect the cells from the battery pack terminals to prevent damage, that’s why tools just stop working, and not slow down as with NiCd or NiMh. Some people assume Li-Ion has flat, constant discharge current and sharp voltage drop when the battery dies and that’s why tools stop abruptly. This is only partially true due to reasons noted above.

Notations
Example: Makita uses 10 cells for their 3 Ah batteries – they are arranged in 2 blocks of 5 cells connected paralelly, each block has 5 cells connected serially. 5 cells * 3.6 V = 18 V, 1.5 Ah. 2 blocks of 18 V 1.5 Ah in parallel = 18 V 3 Ah.

The notation for this type of pack is 5S2P – meaning 5 cells in series form 1 block, and there are 2 of those blocks connected in parallel.

Battery that comes with BDF452HW drill has only 1 block of 5 cells, that’s why it’s flatter than a 3 Ah battery.

Capacity, Energy, Runtime

Tool runtime is proportional to battery energy and tool’s motor efficiency. Battery energy is measured in Watt-hours or Wh.

Energy  = voltage * capacity

For example, Milwaukee V28 battery is 28 volt, 3Ah. Dewalt DC9360 battery is 36 volt 2.3 Ah.

Milwaukee V28 battery energy is 28 * 3 = 84 Wh, Dewalt is 36 * 2.3 = 82.8 Wh – meaning despite having 33% higher voltage, Dewalt 36v tool will have about the same run time as Milwaukee 28v tool. Higher voltage yields higher motor efficiency, so Dewalt tools might perform a slight longer despite having lower battery energy.

Runtime is also dependent on battery discharge current. For example, a simple everyday AA battery is rated around 2.5 Ah. If you discharge it at 0.5 A, it will not last 6 hours, it will last 3 hours at most. However, if you discharge it at 100 mA, it will last over 24 hours. Exact same principle applies to power tool batteries – the harder you drain them, the faster they lose charge.

For example, Moli Energy cells (used in Ridgid, Milwaukee) can handle much higher discharge currents than Sony (Makita) cells despite having a little less capacity.  Sony-based battery will yield less work than Moli-based battery if used under heavy loads such as hole saws or auger bits.

AA battery spec sheet for reference http://data.energizer.com/PDFs/e91.pdf

Battery Chemistry

  • Li-Ion Manganese Spinel (E-One Moli Energy)
  • Li-Po (Lithium Polymer)
  • Li-Ion Manganese Oxide (Sony)
  • Li-Ion Phosphate (Saphion)
  • Li-Ion Nano-phosphate (A123) .
  • Nickel Cadmium (Sanyo, Panasonic)
  • Nickel Metal Hydride (Sanyo, Panasonic)
  • and many many others….

Cycle Life

One of the most critical parameters of any battery is cycle life  – how many charge-discharge cycles a battery can withstand before losing a certain percentage of capacity. Batteries always lose capacity (do not confuse with charge), whether stored or actively used. Various chemistries lose capacity at different rates.

I found that Moli Energy manganese spinel

Cells used in batteries

  • Bosch Litheon 36v – Sony US18650VT
  • Bosch 14.v/18v – Samsung INR18650 13Q (1.3 Ah cell / 18 A max)
  • Bosch 10.8v/12v Samsung INR18650-13P (1.3 Ah / 10 A max)
  • DeWalt NANO 28v/36V – A123 Systems LiFePO4 M1 cell
  • Dewalt 18v – A123 APR18650M1
  • Dewalt 7.2v-24v NiCd Sanyo/Panasonic 1.3 – 2.5 Ah cells
  • Dewalt 18v NiMH Sanyo 2.6 Ah cells
  • Hitachi Li-Ion HXP – Sanyo UR18650SAX
  • Makita LXT slim 1.5 Ah – Sony SE US18650OV
  • Makita LXT 3Ah – Sony US18650VT
  • Metabo Lipower – unknown, same as Craftsman’s
  • Milwaukee V18/V28 series use MoliEnergy IMR18650E/IMR26700A cell
  • Milwaukee M18 – E-Moli IMR-18650E or Samsung INR18650 13Q
  • Milwaukee M12 Samsung INR18650 13Q
  • Ridgid XLI – same as Milwaukee v18/v28
  • Ridgid 18v – 18650 version Emoli or Samsung
  • Ridgid 12v – Sanyo UR18650SAX 18650 cells
  • Ryobi 18v – Samsung INR18650
  • Sears Craftsman – Samsung INR18650 13Q

Saphion phosphate is made by Valence but the cells are manufactured by Pacific Energytech in Taiwan.

Phostech Lithium (a subsidiary of Hydro-Quebec) is (claims to be) the patent holder and plans to make a battery for Bosch. NHH of Japan also says they hold the patents.

Safe chemistry types

  • Cathodes using Nickel-Manganese which include:
  1. Sony “V” (or larger “VT” 26700 size)
  2. Emoli “IMR-18650” models
  3. Konion
  4. BionX

These have 3.6 to 3.7V nominal & 1400-1600mAh capacity. They can be charged up to 4.2V, and seem to have discharge rates of 12-20A based on which spec sheet you read.

  • Cathodes using “Iron Phosphate” made by Valence’s Saphion & A123 Systems that has a Nano version for more robust charging/discharging performance. These have 3V nominal and lower 1100mAh capacity for the 18650 size cell. They can be charged up to 3.6V and have 25+Amp discharge rates

E-moli specs for Milwaukee V28/V18/Ridgid LXI

Specifications of the IMR26700 Cell
Cell Type: IMR26700 Manganese
Size: 26.4mm diameter; 70mm length
Weight: 100g
Capacity: 3Ah
Standard Operating Voltage: 4.2V – 2.5V
Energy Density: 285Wh/l
Power Density: 1500W/kg at 20 seconds
So, let’s reveal the truth:

Ryobi

Line: One+
Model: BPP-1817M
Chemistry: NiCd
Voltage: 18
Capacity: 1.7 Ah
Side note: feels like 1.3 Ah, and I think they use second-grade materials, that’s why they are so cheap.

Line: Lithium
Model: 130429001
Chemistry: LiIon
Voltage: 18
Capacity: 2.4 Ah (unconfirmed 2.8 Ah)

Ridgid

Line: LXi
Model: 130377001
Chemistry: Li-Ion E-moli
Voltage: 24
Capacity: 3 Ah 6S

DeWalt

Line: XRP/XR+
Model: DC9096, DC9091, DC9071
Chemistry: NiCd
Voltage: 18, 14.4, 12
Capacity: 2.4 Ah

Line: XR
Chemistry: NiCd
Voltage: 18, 14.4, 12
Capacity: 2.2 Ah

Line: “regular”
Chemistry: NiCd
Voltage: 18, 14.4, 12, 9.6, 7.2
Capacity: ~1.7 Ah

Line: 36V (Nirvana)
Model: DC9360
Chemistry: LiFePO4, nanophosphate
Voltage: 36
Max cell discharge rate: 30C
Capacity: ~2.3 Ah 10S
Line: 28V (Nirvana)
Model: DC9280
Chemistry: LiFePO4, nanophosphate
Voltage: 28
Max cell discharge rate: 30C
Capacity: ~2.3 Ah 8S
Line: 18V Nano
Model: DC9180
Chemistry: LiFePO4, nanophosphate, 18650 size (smaller than 28/36v tools)
Voltage: 18
Capacity: ~2.2 Ah 5S2P

Milwaukee

Line: “regular”
Chemistry: NiCd
Voltage: 12
Capacity: 1.3 Ah

Milwaukee
Line: “regular”
Chemistry: NiCd
Voltage: 14.4
Capacity: 1.7 Ah

Milwaukee
Line: “regular”
Chemistry: NiCd
Voltage: 18
Capacity: 2.4 Ah

Milwaukee
Line: V18
Chemistry: Li-Ion E-Moli
Voltage: 18
Max cell discharge rate: 15C
Capacity: 2.9 Ah 5S

Milwaukee
Line: V28
Chemistry: Li-Ion E-moli
Voltage: 28
Max cell discharge rate: 15C
Capacity: 2.9 Ah 7S

Porter-Cable

Chemistry: NiCd
Voltage: 19.2, 14.4, 12
Capacity: 1.3 Ah or optional 2.0 Ah

Bosch
Line: Litheon
Chemistry: Li-Ion
Voltage: 10.8
Capacity: 1.1-1.3 Ah

Bosch
Line: Litheon SlimPack
Chemistry: Li-Ion Saphion/Konion
Voltage: 36
Capacity: 1.2 Ah 10S

Bosch
Line: Litheon Brute 18v
Chemistry: Li-Ion Sony/Konion
Voltage: 18v 5S2P or 5S (slim)
Capacity: 2.6 Ah 10S2P

Bosch
Line: Litheon Brute 14.4
Chemistry: Li-Ion Saphion/Konion
Voltage: 14.4 4S2P or 4S
Capacity: 2.6 Ah 10S2P

Makita
Line: LXT
Model: BL1830
Chemistry: Li-Ion
Voltage: 18
Capacity: ~3.0 Ah (10 3.6v 1460 mAh cells in 2 rows)

Makita
Line: LXT
Model: BL1815
Chemistry: Li-Ion
Voltage: 18
Capacity: 1.5 Ah

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Cell comparison: (M1 = a123 for dewalt, e-moli = milwaukee v18/v28)

http://forum.drc.su/userpix/3_a1001895208compare1_1.gif

Found this useful site about various batteries http://progressiverc.com/Research.html

Credits go to guys at RCGroups.com and A123 reps.

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