Bosch Power Tools launched the Bosch CORE18V battery at World of Concrete 2017. Ten high-density Bosch CORE18V cells are welded and connected by rails, which Bosch claims provide 80% more power, longer run time and better heat transfer than previous-generation Bosch cells via updated CoolPack technology. The Bosch CORE18V battery is 100% compatible with all 18-volt Bosch Li-ion tools and chargers.
"Bosch looks at battery power from the user's point of view. What do users want? They want more power and a more compact size, and that's what the CORE18V is all about. The CORE18V represents an important part of Bosch's efforts to build an end-to-end product system part, it delivers exceptional performance no matter what the job. Based on higher power and run time, as well as backwards compatibility across the entire range of power tools, we believe this is a step further than currently available battery power systems."
Theron Sherrod, Product Manager, Robert Bosch Tool Corporation
Bosch Core18V uses Panasonic 20700 batteries
The "core" of the new Bosch Core18V battery is a Panasonic 20700 battery. These are higher density, higher capacity cells that can deliver more power than conventional 18650 cells. We've seen other manufacturers use these batteries – the new Metabo LiHD batteries come to mind. While it's a huge leap, Milwaukee will move further toward 21,700 cells in the near future.
Larger batteries seem like a natural transition for manufacturers looking to squeeze more power out of their packs. In the case of Bosch Core18V battery packs, they can now draw up to 1440 watts of power, whereas current 6 Ah packs can only draw up to 800 watts. This is where they get 80% more power stats (1440/800 yields an 80% increase).
calm under pressure
The new Bosch CORE18V battery features an updated CoolPack design. It manages heat in a more efficient manner by separating each battery into its own compartment. It's not just about physical separation, though. The resin Bosch uses in its CoolPack absorbs heat to draw it away from the batteries, allowing them to run cooler.
It also uses welds and copper to facilitate faster energy transfer between cells (also known as lowering resistance). Copper offers a dramatic improvement in energy transfer compared to other metals, and welding is a significant upgrade over simple soldering techniques.
So what about performance gains?
Reciprocating Saw Test
I'm using the Core18V battery with Bosch's newest 18V reciprocating saw, the GSA18V-125, to see how it performs compared to Bosch's current 6 Ah battery pack. No matter what battery you use, you'll want to check out the new formula. It's an impressive upgrade for Bosch.
As far as testing, I did some controlled environment cutting in a 2 x 12 PT, both clean and embedded with nails. With 10 lbs of weight to ensure consistent downforce, I made dozens of cuts to put the numbers together.
The Bosch Core18V battery did provide a performance boost when all the wood chips were out. In orbit and non-orbit modes, the time gain is approximately 0.4 seconds or 4%. That's a far cry from the 80% Bosch claims, so what's going on here?
This test does not put the saw in danger of stalling, so neither battery will use all available resources to keep the blade moving. If so, the package would be much hotter than it is now. However, since the Core18V can call out 1440 watts of the 800 watts of a standard 6.0 amp-hour battery, it means that future cordless tools from Bosch can be more powerful—just because the battery can deliver more. This test shows that even if you don't put a lot of stress on the tool, your performance will improve slightly.
grinder test
From there, we also did some testing with a Bosch 18V Connected Grinder. Running a full battery cycle of the 6.0 Ah and Core18V battery packs in the 5/8" rebar gave a more in-depth look at the differences.
The fastest cut we could make with the 6.0 Ah battery was 18.3 seconds, while the Core18V managed 10.7 seconds. Cutting speed increased by 42%.
For runtime, the 6.0 Ah battery pack slashed 15 times, while the Core18V finished 21 times—a 40 percent increase. Even just looking at no-load speed, the Core18V battery spins the grinding wheel 360 RPM faster than the 6.0 Ah battery pack.
What about the future?
Bosch has a reputation for producing high-quality tools that are tough and durable on the job site, but there have been a few categories that have lagged the industry in terms of performance over the past few years. Beyond simply plugging in a new battery pack to power these tools, it also opens the door to more powerful tools. In fact, being able to pull 1440 watts from the battery pack instead of 800 watts opens some pretty big doors.
So what should we expect?
First of all, Bosch is tight-lipped about the development, so it's all speculation at the moment. However, I would love to see Bosch's first 1000+ in. lbs. The drill or hammer drill has been used with the SDS-Max rotary hammer for too long. We can certainly expect a power boost with any new 18V tools they come out with, but these two would be good targets. Bosch's 18V Connected Grinder is actually the first tool they've released that builds on Core18V.
Core18V Slim Pack and 8.0Ah Fat Pack
One of the things Bosch has done really well in boosting the amp-hour capacity is keeping the pack size from ballooning to nasty amounts. Tools like impact drivers and drills can benefit from Core18V technology, but if you can save some weight, you don't really need 6.3 amp hours. The new Bosch Core18V 4.0 Ah slim battery pack answers this request.
We mentioned before that the future Core18V battery may use 21700 cells, and the 4.0 Ah battery pack has it. There are also 8.0 Ah battery packs on the market.
Any chance of using 9 Ah Core18V?
Don't hold your breath 3P pack (15 batteries total). Bosch is very intentional about keeping the size of its 18V batteries small. After all, we're talking about 18V tools. Large and heavy 36V tools are generally accepted, but Bosch wanted to keep the 18V lines manageable. A big part of that is reducing the size and weight of the battery pack. Expect Bosch to continue to develop better battery pack designs and move to 21700 cells — just don't expect the pack to accommodate another row of cells.
Price
If you only want to use one battery, here's the basic pricing structure:
- 4.0 Ah Core18V (21700 cells): $71
- 6.3 Ah Core18V (20700 cells): $159
- 8.0 Ah Core18V (21700 cells): $149
At the time of writing, the 6.3 Ah and 8.0 Ah batteries retail for the same price, making them a pretty easy choice.
Starter kits, multiple battery packs and tool kits that come with Bosch Core18V batteries are also available.
the bottom line
The Bosch Core18V battery pack opens some important doors for Bosch's current and future cordless product lines. Our tests have shown a significant increase in power and runtime with the Core18V battery pack, and we are still in the early stages of designing Bosch cordless tools for batteries that provide higher power output.
Bosch CORE18V battery characteristics
- More power than previous generation Bosch batteries (up to 43%)
- longer runtime
- Updated CoolPack technology for better heat transfer
- Compatible with all Bosch 18V tools and chargers
Bosch CORE18V battery specification
- Voltage: 18V
- Li-Ion: 20700 (6.3 Ah), 21700 (4.0 Ah and 8.0 Ah)
- Amp Hours: 4.0, 6.3 or 8.0
- Vehicle Fuel Gauge
- Temperature Range: Down to -4ºF
- Price: $79 – $149