The D250SE (CTEK Part No. 40-315) is a DC to DC fully automatic charger that’s designed to charge a Service Battery and is powered by the alternator/starter battery. With dual inputs the D250SE is also solar compatible (a standard solar controller is not necessary). The D250SE charger supplies up to 20A of power to any 12V lead-acid or lithium service battery from 40–300Ah. It also works if the starter battery and service battery are different chemistries, for example if the starter battery is lead/acid and the service battery is lithium. (Note: a service battery may also be called an auxiliary/aux battery, house battery, secondary battery, or backup battery.) This is a great charger for our V1 and V2 Lithium Deep Cycle Batteries.
Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 10 - Jul 15
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
CTEK D250SE 12V Smart Charger 20AThe D250SE (CTEK Part No. 40 315) is a DC to DC fully automatic charger thats designed to charge a Service Battery and is powered by the alternator starter battery. With dual inputs the D250SE is also solar compatible (a standard solar controller is not necessary). The D250SE charger supplies up to 20A of power to any 12V lead acid or lithium service battery from 40300Ah. It also works if the starter battery and service battery are different
Dual Inputs
The D250SE CTEK Charger has dual inputs and can charge the service battery from the alternator or a solar panel or both. The charger is designed to work with smart alternators and can still operate if the alternator is shut off but the vehicle has access to solar or wind power. So it can use power from the alternator, solar panel, wind power, or any DC power source can be used through the solar input port (within voltage spec). The D250SE can also charge the service battery from the solar input and the alternator in parallel using its built-in regulator to save fuel.
Optimum Charge
Continuous charging while the vehicle’s on the move means the batteries are fully charged in the shortest possible time. The built-in temperature sensor compensates for hot or cold conditions to prevent the battery from overheating or overcharging, so it always gets the optimum charge.
When the service battery being maintained is fully charged, the D250SE will automatically redirect overflow charge power to top-off the starter battery. The D250SE can maintain a stable output up to 20A to vehicles fitted with smart ECU controlled alternators.
LITHIUM
5-Step Program
- Accept*: Tests if the battery can accept charge. This step prevents that charging proceeds with a defect battery. (*Step 1 for lead/acid is Desulphation)
- Bulk: Charging with maximum current until approximately 90% battery capacity*. (80% capacity for lead/acid.)
- Absorption: Charging with declining current to maximize up to 95% battery capacity*. (100% capacity for lead/acid.)
- Float: Maintaining the battery voltage at maximum level by providing a constant voltage charge.
- Pulse: Maintaining the battery at 95–100% capacity. The charger monitors the battery voltage and gives a pulse when necessary to keep the battery fully charged.
Video about D250SE Charger
Specs
- CTEK PN: 40-315
- Input: 11.5–23V, 25A
- Output: Max 14.4/14.2/14.7V, 20A max
- Back-Current Drain*: Less than 1Ah/month
- Ambient Temperature: -4°F to +122°F (-20°C to +50°C)
- Battery Types: 12-Volt WET, EFB, Ca/Ca, MF, AGM, GEL, Lithium (LiFePO4, Li-Fe, Li-iron, LFP)
- Battery Capacity: 40–300Ah
- Insulation class: IP65 (splash and dust proof)
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.8 ★★★★★
Based on 1217 reviews
Sort
Product Reviews
★★★★★ 4
Tuffy Desert Phrog vs Lola
Color: Green Leaping Phrog, Color: Green Leaping Phrog
Just a little background about my dog. Lola is a 5 year old corgi-terrier mix with jaws of steal. Lesser stuffed toys have met death in under 5 minutes. Tennis balls last less than a day. Rope toys that do not have frayed ends might possibly last a week (frayed ends never stand a chance). The only toys that she has not managed to destroy are her Kong, a Kong bone, and a racquet ball. I figured I would document the life span of Phrog (Tuffy Scale: 9) before making my final judgement on it’s durability.
Day 1 - Phrog Arrives! Lola was very excited about the arrival of Phrog and immediately went into destruction mode. Phrog did sustain a little damage before we were able to bribe her to drop Phrog and get her understand that he was more fun to play fetch with than to mutilate. The white you see in the picture is not stuffing, but the second layer of defense for the toy. The fact that my living room is not full of stuffing and I didn’t have to pry a squeaker out of my dog’s mouth, I’d say Phrog wins the Day 1 challenge.
Day 9 - Phrog has sustained a little more damage, but not anything life threatening. His side wound is a little bit larger and one of his eyes is half ripped off. For safety reasons, I am going to finish removing the damaged eye and some loose thread from various places. Other than that, Phrog is still holding up and holds top toy spot. I have also found him very useful for dealing with anxiety; the squeaker can often distract her from her stressors and Phrog takes the abuse of her frustrations.
Day 16 - Phrog is starting to show signs of mortal wounds. Lola has made it through the thicker layer around his arm and I can see the stuffing. It is only a matter of time before gets all the way through.
Day 60 - Phrog still lives!!! I have done some surgery on Phrog to reinforce the fabric around his arms, but Franken-Phrog is still the favorite of all of the toys. She will even get brave enough to rescue Phrog from the evil vacuum when he is kidnapped and tortured. I am thinking about purchasing Phrog II for the inevitable day when Phrog goes off to the pet toyland in the sky, but for now, there is only one Phrog for Lola.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on July 6, 2018
★★★★★ 5
Super tough
Color: Red Warthog
My dogs love these toys!!!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 10, 2026
★★★★★ 5
Long lasting play toy!
Color: Multicolor
Tuffy toys in general are great and they are a pretty good deal on Amazon. They are not indestructible, and if your dogs use them as chew toys they will eventually break through. My dogs have had this Armadillo since Christmas (and they do chew on it some) and the only thing missing is an ear. They like to play tug-of-war with it a lot. This is a bigger toy, but even my forty pound dog plays with it. I would not recommend this toy for dogs smaller than Border Collie size. You can make these Tuffy toys last longer if you don't allow your dogs to chew them--when your dogs starts chewing on non-chew toys trade them for a chew toy and when you catch your dog chewing on a chew-approved toy reward them for chewing. Eventually your dog will catch on and realize that if they want to chew there are certain toys that are allowed for that. In addition to being a great play toy this is a pretty cute toy too!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 30, 2015
★★★★★ 1
Not Tuff
Color: Black Yellow Phrog, Color: Black Yellow Phrog
Absolutely terrible and not “tuff” at all. My chocolate lab had this thing destroyed in less than two hours. I would not recommend these for the price.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 11, 2026
★★★★★ 3
Cute but Not Durable
Color: 2PK Green Leaping Phrog
⭐️⭐️⭐️⭐️ Cute but Not Durable
Super cute toy—my dogs loved it right away! Unfortunately, they chewed the head off within a few hours. I ordered a second one because they were so into it, but the same thing happened again.
I won’t be ordering a third, but they still play with their two headless frogs. So while it’s not the most durable, it definitely kept them entertained!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 9, 2025